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Handbook
1993 Edition
NOTICE Addrt$ses, telephone numbers, and ClInl6Ct information Ii,ted in this puNi""tion
are long out ofd81e and may not be valid. You may be wlelo ClIntaei
manufacturer, andvendo~IhrOllgh their lniemet Web <ite,. We regre! th.t If\!:, FCC
connot provide CUm:nl ClIniBCI infomali"" for these businesse<
FCC Field Office 10000Iions and ClInt.er infonnation is no longer ClIrrecl for ",""y
offi=
[J.nuary 2004J
CHAPTER I TWf>.WAY RADIO TRANSMI'ITER 5
CONTENTS
PART (, INTERFERENCE TO TELEVISION
RECEPrION
CHAPTER $ OO'HER INTERFERENCE INPORMATION 17
FRINGE AREA RECEPTION _ 17
GHOSrING .........•..... . 17
OOCHANl'!'l:L IN1"ERFERENCE .... " 17
. .. If>
"
"
COMPUTERS, PAGING SYSTEMS., . .
VIDEO CASSETI'E RECORDERS (\'CRII)
BOOS'TER AlU'LIFIERS ".'_."._ .
INFORMATION FOR TELEVISION
OWNERS 6
INFORMATION FOR RADlOTRANSMIITER
OPERAWRS , 7
INf'ORMATION FOR CB OP£RA'JORS 8
INF'ORlUJION )'OR AllATEUR
OPERAlORS . ,
CHAPTER 2 ELECTRICAL INTERFERENCE . 10
COMXQN ELECTRICAL I"'TERFERENC£
SOURCES....................... . 10
POWER COllPANY ELECTRICAL
EQUiPMENT..................... . 12
DOORBELL TRANSFORMERS 12
CIIAP'TER 3 FM RADIO TRANSMI1TERS , .. '" .13
CIIAPTER •
2
PART II, INTERFERENCE TO OO'IIER
EQUIPMENT
CHAPTER' TELEPHONES. CORDLESS TELEPHONES 18
ELECTRONIC ORGANS, AXIFM RADIOS. 20
sn:REO AND HI-FIEQUlPll.E~'T•••. 20
PART III, ADDITIONAL INFORMATION
CHAPTER 7 WHERE 11) GET HELP .........••••••••••• 21
ASSOCIATIONS . _ " •....•..
MANUF'ACrURERS , .. ,
~'CCOFt'lCES .
•.. •••••.. 21
....•. 22
..
CHAPT'tR 8 f'1U'ER INFOfUlATiON _ tl8
CHAPTER I TECHNICAL INroRXATfON POR SERVICE
TECHNICIANS 41
RADIO TRANSXrrrER MODIPICATlONS ofl
RESOl.VING 1h"I'ERf'ERENCE AT THE
TELEVISION RECEIVER 43
El.ECTRICAL, "If AND AUDIO
INTERFERENCE 47
Acknowledgements
M~'"LiM.: A-ncan Radio Re'-1 I..oeIpe
N~Conn. 00611
EIectr<mio IDlNIt/iIN Anori.;...,
_OC_
111116 Edition
3
4
INTRODUCTION
Thi. handbook hal been produced UI hllp Yl'" ruolv. inl.llrfa_ 1.0
)'OI.lI' ttleviliOll, ate..Or telephonuquJpment. Part I idMl.il'lu lOme 0{
lb. IOOre CllmmOll.autcft otinterfe••",.,.. to tel.vi_ion~kln.ltallO
eont.aln. ilIUl!t....Uonl of variOUI typet ot Interference that m., .ffed
)'O\U' 1.eJey;.ion ..-ption. Recommendlll.lonl to help you.lOQllethe_~
tIl the lntelfe_ and Oewmine an appropn.tIl ......tion ... prcMded.
Part II aM>eem' interl'e_ 1.0 otheT eI«l.ronltequlpment. Retohition"
iDterl'_~m.ll....l1y requi..eoopuatioa betw-. equiptnfflt
owners. Part III provide.~eren"".ro. auiltAnOi from equipment
.....nurtK'Lunln. dilt.ributo.. and .....Ioe tedmkillOl.
'"'" Commiulon Inc:ourapI CUlsumen to be lUre thal their TV, It.ereo.
or ocher ele<tronictqU~lcan oufflCiffll.l)'~undelfrecl radio r...
quen<:J' lienal... LikewiM. tnnJnlilU. operalOl'S m.... Uk••ll _.,.
~10 f'I!du<,e or elimin/lll In,,,,rl'e_ rl"l)m their "'I";pm.nL
PART I
SOURCES OF INTERFERENCE
TO TELEVISION RECEPTION
CIIAPTER 1
TWQ.WAY RADIO TRANSlIIT1'ER INTERFERENCE
11IiI pllltftTl may appear on )'OW" l.eJeo.iNon~when )'OUT lII!t ;.~v.
inc~from • CD, amat.eul'. polite. orOlher t".."Vradio transmiu«.
ThepIIl~..ill only IlPP8I' ..'hen tM ope...u>rll'aMllliu. It may VV)'
.......<Iii.. to lhe type~......~n!fti~\Ou may .... hear lhe
~'.voice.
INFORMATION FOR TV OWNER
'lOur lint step illAI look fix- one or more '" the _ pHlbIh•• IilIted
.".,. and Mlftrlpl 1M r__nded IlliuI.iola n-pHlbIh.. at'l! all
P'll"'ntW _ why,.....~~Itui.e interf<erence.
See "VCR". page 16.
RECOMMENDED
SOLUTIONS:
Repair or repl.ee
Contal't rable Ollmp&ny
","","-"""""
~if ....--d. It '--I. _
tlk't e.bIe """P'V'
Remove or llOlltart eabIe fUnIpUOy
Replace Dr repair
~U8ing ftJaXial cable wiUl
tnlUltinr tranilonners (Qften called
balUnll)
Repl.ce with an outdoor antenna
RepoNt.ion antenna (or beel~
"'"
Nfl 11.
l........u lUters. repair Dr I'epIaee
mali't1nrtioninc amplltIer .. re- 
q\lired. See "llooIur ....plifwrs,.,
-'.
Indoor antenna (.rabbll e-,..)
J\Ior outdoor llII\enna Ioeat.lon
Di&tanre from TV lIWWnltter
VCR OOI1ne<.'tlon
c.ble TV eonne<:tion
-dekd.h-e aplitl.t'r
--
-100:. or open ronnectorI
---
.....
-.....-
PROBLEM:
INFORMATION FOR RAOIO TRA.__ SXITTER OPERAroRS
If)'OU n'Ce;"'.~about interfeftnel! 1'rom)'OllT radio traMmitler
)'OU ah:IuId voIunwily ...... tile..ouUined belo.ror. 'nIiaIN(!' pele""tlle
f'edtral Communic:Ioiion CommiMion fmm dln!dllw )'OU loll do ..
I
n-etomII'lOIl probIenvI~IlOl be tile only __ cl your inurfel'\'Me.
The recommended IOI\Ition~IlOl "......... If)'OUr interleftnce problem
~lJ'y inMalIOW • IIWl\.pua fIItu on tile bKk cl your TV .el at
the anterll'* I.mnir..Ia. f'oDow iMtallatiOfI m.tnootlona Ulat~tile
_.
Ifthe tiIt.er doea IIOl wort, J"DU ahouId kate tile -..«or opln&OI' cltile
rw;IiDInnamit~Give l.bem • """" cl tile Itadie n-lltiK OpIoralw
laf......ue.~cltlliahancllook.lfJ"DUdo IIOl kMWwho tile.....,..
.. rhedl )'OUT neichbor.' roof. and ,..... for OM vi. tile _ ..a-n
bekIoI. Arry ndio~uerwitlIin 500r-vi. JOVr I ' ...... ean - 
interf~Ifu..re are aewnI anl.iKINoI ill JOVr rlEChboi hood, C'ClIl&arl.
tile0"'_vi. the _ -'-)'OIl.AIoa.uerapl to dfUollhir..~tileneat'eIt
trwwniU.er ia~operaud...ben )'OUT TV ia~the1nt.ft1"~
Your neClobo•• mar abo be able to beIp J"DU locate tile opln&OI'.
lr tlle interleftnC'e eomin.- alter tile IzanamiuiK opiK1lI.OI'iII'l~
our~lIOIutionI. C'()I1lart JOUr~1lWlul"..a.urer or •
qualit'"Mld .....b tedmician for altemative -..Iutiora
The~p)!'1_ are Wi_ ....... wto' II'aIlIIIIitIiK'l _
inlerfuu_ t..,.,the Ie oded dutioIw.lf)'llU need...-.nee od.h
lIlY cl theIe~o:'CIftIaft )'OIIT deaIoer, equiplllE'"~,...
klCII U'lrM' "1« repIir ahcIp.Na1'E: no lSlLLEGAL TO USEA LlNEAR
AJlPUFIER wmI C8 EQUlPIlENT".
INFORMATION FOR CB OPERATORS
Hannonirl or 1pUriouI_' -. lmull.~r niter ill the
tIaRImluft" __~
RECOMMENDED
SOLUTIONS:
Rtute~In another~
p~fef1lblyaway (10m nearby
~Iltt,
W
Replaoe il with •~
antenlll.
Sep.note horizontaUy II(llr..po8Ili 
ble from y(lur neighbor" TV
antenna
w
Raile )'OlU' antenna', height II!
necul'V)' ..ithln IfpIIlmII& (00 rO'et
abo7Ie il'\lWld. or up to lJl reet I\iiher
than~point III thelItnIrtu~
upon whidllt ia mounted.)
Reduce 10 4 "'IU.L
~.........ulter dlaIeiIJ 10 a
rood earth groulld wit1I large
diameler wire or mpper Itlap.
TWlun the ICft'n holcinr the
ehuIiI and ....~.Do *"
.....tMt> ,..itq."""'irI_
or_" I Ill.
PROBLEM,
IIkpIIy inIuIled equipmerc lJIM.
VIOl.ATES TYPE NXEP.
TA...va: RULES 1UdI .. I'Xtno
~utft'Ml MuehmentI,
rewind dmlita or I!':ltnI ftitdw
'-,. ;.
1Acal1on 01 antenna
~III tnnenUlter OIIlpul power
~~4_11imil
-~-
INFORMATION FOR AMATEUR OPERATORS
PROBLEM: RECOMMENDED
SOLUTIONS:
H......and JP\IriouI t!ftlis. IIlIl.llD •Iow-~t\h.er in tht ....
--. l.eIInahdh.orin !he-mllink
u>!he~lwRr
w
lllILIIII.tIherbft_!he~
~{e:Ilcit«j and tht Inp.ot 10 !Joe
ampIiIl.er. A-.dflh« thould be
~at tile ampMe'. GUtput.
u.~muimum pooow Ie¥N Conoh1. t8t& by~,aur
pooow to del.m:nine tile dl'e« lhat
~power wiD ha.-. on the"-'
~interl~.._ It pooow
opention& reduc. or eliminate Ole
interl~rence,you~w\ah 10 c0n 
sider~&I. tht lower~
....henever poMible. Thi&~Iltlp
~.to~harmony to thlt
neighborhood.
High gain or directional antenna ThIt etrf!ct.iY'll radiated pllW('r (ERPl
~high pin antennu~ntedat
maximum pO'NU 11M!1. can c:reat.e a
"bIanbtlllll''' l!tI'ect. Considltr Il5in("
anon~anten.na or rl!due 
ed opl'ratillll' JIOW'tr.
Pbor~Ground tranunilW" 10 a meWlic
cold __ pipit or a f\"CIUM rod
driven II. __ 8 felt Into Ole
e-md- GIVUIId lead "-kI be at
Ieat 110 ...a.. cqJp8' ribbon or
.....
t-IiIurf_ClClm
mjo
,_an!....aabloe to Mfp~~t1loeir
inlftJ....tiXE probIm. Fla> •Imcein~.1IlllmIllil.l.MinJ'VW' ....
_!JoeAmeriean Rdo lldli;)'~N~CoiInKtiM 06111,
or !be-.FCC aftke IiIlaI on pace 16.
COMMON ELECTRICAL INTEK.'EKENCt: SOURCES
CHAPTER 2
ELECTRICAL INTERFERENCE
PATTERN BPA1'TERN A
The .-I. mmmon I<lIJJ'<'('Il d electriuJ interferellte in the home Ilft!:
DoorbeU U'U!8fo""""" (See pajI1' 12)
--
Elertrit bIankeu
...
HNtinc pO
LiPt diuwer eontnlb
S.iuh eonlKU,.u~b... th_ found on di.h.....b.,n,
~and aWr bome IIp(ItianceI
Aquarium or~hoeetft"I
........
rw I.... ClClfIrolI
Smoke p. i;*.on or dei....on
H__
~.-.-uol deoita
P.ttern A """oe Illl\,Y appear on J'IUI'" u.IeviIion KI'ftI\ ",,,", )'llUI'" let iI
reartinr to an eIectrieaI~~in or __ JOW' home. I'lluem
Bean be -.d by ...tiD frequeney enerJJ 1"''''"lUd by (lO"'eI' Ii.-or
power line equipment.. One "V to de\.ennine II'the lnt.trleftlX'Jl! iI conlin 
I'd to )'OIIr home iI to ched< ",hether your neighbon are Il18G apeliencillg
the problem. If not, theinterle~ia ptObably~by IOIMChlng
within your horne. The operation d eleWic ....... hail' df)'era, eleo:trir driIk
and .".. alM aUIie temporary interferellte pl"Obll!nu. 'roll mI,yd_to
tolente tlM!tle typN d inlerfe1"f!Tlee sillte they llTlI lemponry and otlen
apl!lIIive t.o elimilllUl.
Lf«hta: nor-t ..... men:tU'Y '-.pol'
N_....
f\;Npr eomp&n1 eleclricalequi~(See plIC'f! 12)
I.-(OJ._ eled.tbI inuorfet"elXle IIOUm!lI indude:
LoGIe ru.. ..~wiIine~
Se.b.~
~~1UdI. tnm.
"""""""
Eledril: Ilenl'eI
"""' 
-~
........-
Jt'AR/o'ING
TO AmiD AN £LECTRlCtL SHOCK. ELECTRlCAL OR ELEC
TRONIC EQUIPMENT SHOULD ONLY BE MODIFIED Bf
QUALIFIED SERVICE TECHNICIA/VS.
hrtable AM ..dioIare~t.o~int.erl"ererw:e. Ute)'OUT AM
I'lldio to eonduct the rollcrwing "\.e5l.." This tellt 1M,)' help )'OlI to lo<:Me the
devioe that iI c:alWJ'l( lnterfe"""""'- to your TV.
'J\om on the portAble AM nod.iu ..... plaee the indkat.or betwetn lUltion8
at the \ower end o:i the dial until)'Oll hear e\.atle or a buulng aound. Move
from room 10 room lIlIing the radio ...detection device to locate the IIO\lfft
rlirurle_The nolM will be kJo.>dIoet in the room where the~rwoee
ill oririnat.inc- Unpluc each~the devlcft pn!riQuaIy mentioned. one at.
time, unt1l theinterf~1Ml8di..pp".... from your TV. The device that ,...
~rill call&ing !.heInterl'e~must be repaired or repI..M.
Anotber W1\Y to dilaM1' the aource ofinterlerftlOt to )'OUT TV ill toc" to
t1Ie main ru.e or rimllt br-Io:8 bcllt in )'OUT home. Remove _ I'uae ••
u-. or ahut oIf _ eIrNit bi ...... time. ..... _ Il' the Intuf_
I""~((!.heInterf~~not dieaflpNr, I"l'place LIM l'uee or tIiJ'II
t1Ie cimIiL bi e .... block on. Ccdinuoe t.hie IN IIlltil the Int.et ruenao
r " ....
WMlthe rimllt !hal_Wi"!.he powe' to the TV ill tlIrMd oIf, pluc tM
TV inlo mach!rcraa. n.iawi!~)IIlUto dp .uiue Illhe inwftoa tId
ill beq:iwti t.ed~attevn tMt ia pc ued by the __rimllt. 7llID'
TV.
If the illter1eJftlOe pattern diMppee,. 1'rom)'OW' TV _ when."-.
le_~1Ir.c:ireuk bE ......tDmIId dI. roto the..,.,. t.lrIIr.."'ei..... tbe
~,.-"",""bJ the diRoaneded ciralit. LooIl. far UO'~thede••
prwiouaIJ' mentioned. 1f)lOU find~01 them. ftrIt, >qliace tbe~1Ir
twn tbecireuilbo I ...~t-k...1"Den .......tbedericlll!. ;+'''''01_
q Ole pt'Oblem.lfIeftl'&I de.itw are Oft thiI cimIit unpllll them one '"
• lime until Ole irlc.eI"I'uence ctiupp-ara.
It thiI proeeu doH not ..-rthe Illll.lft 01 )'OW' int.erference, uk )'OW'
immediate neighbon Ifthey~alIo~ivinethe inWference.. If110, )'IlUT
nelghbof!l mllY~tto ron the IIliJne dl'C\llt breaker leU.
POWER COMPANY ELECfRICAL EQUIPMENT
If)'llli determine that \.he interfe>"!!lCl • not cauaed by any deotlellln)'UUl'"
home or thai. fl/I JOW' nelcftbor(a), __IJJe R:i • ice departmeI'lt fl/I your
IoraIpoooer~.naer ahoWd ilh rw-e the ploblenl and tab-.ep.
to I!llITeCl it. 'Ibu~want to -..ethat JOW' JI'I"I'C" eompul)' c:hecb far:
~h'-d._
LoaM 1Ir Ilnbonded hardware
~!'rom df:fectM IigIIulinc &rft8Uln
DeffCtio<e tnnII'ormen
Ir the flO'I'W~doH not reoEPOIId to JOUr~_. 't......JOU
m.,y oontad. tbe ......... FCC of!Iee tor help.
DOORBELL TRA.NSFORM.ERS
Doorl>eU t.rar1Il'onners can _1nt.erl'crellCll to )'IlUT t.e1evWon~
ThiI typeolinterlercllC'eia~by PlItl.enl A. o.bc>orn on.~10,
whidl wiD a::.-r at appnnimacly &eW'lI Ml:OIld inl.cn-al& It miebt be
bel;:IuI to "",lei .reI wb;y Ihia omn.
lr • ckubell buUc- Ie pl d too~or it tbe button beceoufi .wok,
tbe ckubell pllftT lI'I!lIIormer een CIS I eat, ......m huerd. For
JIf'lllec.'tiOf dcoI1IeD trell",'WlilPlI include en IlItwnetic ..t1!tJ' IWitdl tbet.
bIme dI the t....1&."16 ...... OIU' ·i,. occure. After Ole ..ntdt
aulOnVllic:ally .....,. the trenII'w_, dI, it will COIIIl and twn itaell' t-k
on. Thie IlltOIllIlii:mJoIl~~.IITIIII ere whicb__eecuiCloI
Intu1e,ence. ThIe temper "n'e~deYb can bw:ane del«tio<e and
I"l'*'t to~t.euipCl_~Np'""ien,.when the UIi.m",er
ie Iocel.ed ia' hot ettk. InterlercllClP problenli!'rom doortIe& an gentI'lI1o
ly ool'l"eCted by havirc an elertrieian rep'-tt the lnMtorTllU. The doorbeU
button Ihoo.LId alto be eumined tor jemmi..-, end repleced It~fCtiV8.
CHAPTER S
PM RADIO 1'IUNSMJ'M'ER INTERFERENCE
11liI ....tem IlII\Y appnron)'OUr TV ICJ'Hft when~.ClIlIIed
by lIipalI tn>m lLrI PM ndio U'aIlIm.itter, The CommIMlorl~Mw
Fill: .ulon appIlnlnu 10 oonaIdeT potent.iaI wide~Int.erf~"'_pro 
biemI and mlnlmile lht!rn bJ' llt\eding a Jl"lPt' 1ftIIatr'Il«er Iomlon. FM
.....CIptnIl(n _~10.eapaold to aII.-V1b1eiNa••daun 
pIaiJIu _ the -'on ber\rw operaline. 'l'hemore. )'IlU ahoo.ild ,.,... ('Or> 
tad. the PM 8tallorl iii....... (,'),if{ Opentor or ClIW EngI_ ror
~If only TV Channtl 6 • affected.)'OIl ahoo.ild -uct the TV
......
There an t~_prOOIenIIlhat inwofvoIl PM~
ne nr. poWtui IIIol\Y ariae wben)'Oll aN • I 4.q a diIIMl TV alpaI
.a_ PM __~openWwin)'OUl"_lburTV....... IllIQ'
• ; .1 to the -tIJ PM Jicnal, ....... .IBIQ' "'ape a )'OUI"TV Ill••
It• ......,..... 10 I'«lJIPIiaau.TV 1IipIII_c.lb' (I ,tRio'-...."""
witIliII • IiIftlted~~milN (or ndiua)~the tnnInliU.er, AIv TV
~1&1.. mDN ''frirlIoe'"~AJtJiouP 1nIwe_~
tB.......Waa"". \eo"..,,..--17 .......Stc a..tap.L 'I"aat.
........,. P" 10 iIur".a 5 III I.' ,aftatk-.r all
f')I buod rc;..'!..mt«~a kiply diNal ! w ....__
~jrc ..._ publei•• n.a.w&,.' <tithe J")(__••aood
...".<tI InIui t about int<!I ""axe~ledNiq _ If,.... ....
...wledorkh !.he leIplIl.... tolUlt'PI I0o:III f'OC ol'I'lc-.liIt.ed
ia~1.
A IeClOlld problem may ariae ...·hen )'011 lIltempl 10~vea TV liin&I ...ith
a booIt.er amplifier inetalled in your ............ lylIltm.~ampIi1'",...
.... _1Ufd. to~by Itrnng.-royFM aJcnala. WhenO'\~
~)'011 ahould inIlalI all F1lI band~niter or a umabIe FM re 
j«t.ion trap in the r-nine bet.._ )'OW' antenna and booMer. In extreme
_ illl'lQ' be "otl "J to inRaIl alM!t'Onll nit«. If... plxe the~
fIhft' In RriH with the tint. -. or ... lhe input terminaIt 01 your TV
~__• If)'OUT booIur amplilier • def«Uve or~it. CXIUId
_Deileie....~JVUI'.iti/ehboihood. h ....~..".....h
"'-'a'~or rtplartd.. Seoe~16 tor _Information 011 boo&ter
.....,ti6t...
CHAPTER 4
COMPUTERS, PAGING SYSTEMS, VIOEO CASSEtTE
RECOROERS ('"eRa). BOOSTER .uIIPLIFIERS
COMPUTER INTERFERENCE
Comput«~will normally dl.nlpt only J'OlW TV recepUlwL
~oiIt.r~bet_theTVand<:Orllp&Mr..-y..-....the.."""""
~,)'OW' CIJIIIPIUl' fJSlftD ..-y _ intefft. ella! to JOIU
~TV Ie p<1on. Irthia.......n. yw _ requimf to cIiIclonlinue_
~J'OlW computer I)'IlelII until you can om.... e the lIurfua.... problellL
ConMih ,....,.. OOl'lW!f', IftflULIII ... the~deoaIer /III'~.
PAGING SYSTEM Il\I'TERI'ERENCE
You mq hear the tone ... Wliee t.I'llnIImiMion from • one-q' eomIllOfl
ranWr~Iyat.em......u.w~)'CUTTV IIl!t. The~....
quire&~.~opmuora to relIplIIld to interlef'b'l'! t.&Uad by their
~....hiIe in the do!veIoprnentallitenlirc piOC If\he ope_
raJlI to reIpl)l'Id to your~,you may oontart )'CUT \oo:lol FCC otr"",
\iit.ed in CIIapw 1~thi! handboolc.
vlm:o CASSEnE RECORDERS (VCR.)
VCRI~receivelnt.erfere~from nearby radio tranBmltU!no. 1b dete...
mine Ifyour VCR la reeelving the inU!rferenee and not. your TV, tum your
TV on. and you.r VCR off. [fthe int.erferenoe c:ontinOOB, \he unv.Wlted ligna!
rM,Y N enU!rine l.hrough either )'OW' TV llet. or &ntc"Mf ')'lIU!1n. If the [n.
terl~diaappean., your VCR ill pidrlna: up llle Iignal.
'"'"" IU'e -"".....,.. that lnterferetICe m&,)' enter • VCR.:
Dil'ecUy throurb llle VCR (:fIlO! to n. lnlem&l ('(lmpl)I'IeIlti
_~VCR~&I'Idlor eablel
- 'Ilaroucft llle~«lnI
A ?± aolulionI lndudr.
_ Replacirw~wireI wit.h aJUiIl~
_ flqIIaobll pIIIlHlII. wc:tIn wit.b &Cft'W'OII ('OIuwc:tln
If u-e do not -" the VCR~for alWmMiYe
--
BOOSTER AMPLIFIERS
A ....nety III potl!",. IIIlQ'~... JVUI' TV --.be ..III~
at ,J'...... w..rlabd. Sc . '_awwr 1*1ICnI".y 1ppNr,..lhe.. 
~black out for Ihort~IfJVUl' -1)'IUm _ a~
ampliIRr, liaconnect it. Then eonnect lhe _ cfufttly W JVUI' tfWri.
lion IICL IflheinLIrl~....W-~hfie)'OW~~~
..~II)'OWTV.«JrInected toa MMt.b'AntennJ,~le<Jeion(WATV>
.~,and is ..-iv\ng~rfere_I:Olltart the bw1dinr mtIIagl!menl.
If you own your TV anttnna 8)'11Wn, atttlllpl to locate the an>pli1ler.
AlIlp\i1ler'l ..,. b<lloeated:
On the bKk III a TV
On an outdoor antenna
Along a distribu.......ire that tJoooIl !he an1ftInr, to u.e TV
In a <::1o:lO.-~be iilCill. auk .. prq'II!
If the int.erferenoe pcr ire '«ilh JVUI' ampMer~andt.,,,,~­
cd. you~be re«i,ir:C~rt.lm a nelcbba '••'cN...... If~
ntIcftbnn 1lith bolnttft-.,,~·r*l.aD~1nt6&.e.leC, 1M mewit1I tile
_ -...inurlCftllC'e it prot.bly Ole me with the deI«tt¥e -P&r.
~{'O"1']Ql1e in 1M~with an amplifier will~to
diIc<lnned. and~tMir~,me at a time, to ciIc:over whicllone
itdef«tive. Lneal.inIadel'ecti~an>plI1ler ean be difl'leult. The TV ante1\ 
III cmlnected to thedeI'«ti~an>pli1ler can I'lIdiate interference 0'VI£l' an
eolil"ll neighborhood.
800.ter and dUlLrihutJon arnp1it>erl are alto fUIol.'t'Illible to ne&rby BdIo
U'aIlImitter fil[nalI. 'I'M in..,u,'km cI tilter'1 before and~lbe amplifier
will normally eIirninaW thlt kind III lnlerlflot_ Ifthe amplil\er it doee
I.ll the TV, only menJ~belore the ampMer mlO' be required.
CHAPTER S
OTHER INTERFERENCE INFOIlJlATION
FRINGE AREA RECEPTION
TV ........., intMdfd to _~onI)' within • limited distance
~tMlr tr&nImit.terI. My TV reception ber!lnd thia~III o:alltd
'"fringe uu" reeeption. Althoujft fringe aJ'H tienalI~be 1I&l.Wadt.wy,
t.hey an! weak aignale that an! highly ..-ptible toint.erfe~roeeMIl an!
not prott<:ted by the Commislllon. If the inlltallation 0(.dil"ectiofla1 anten 
na or lUt.er on)'OUT TV IIet fll!l.l Ul eliminate thelntHl'e~""",probltm, ((In·
IIIdera1~~TV~Cable. ateUite, MIl TV tTamlaton an!
pouibIe a1temat.i-.
GHOSTING
Two ronditIorw may __• doulMe irn:Ice~_ TV PiClJ-~
to appo!aI" QII )"lIIP" _G~may "'" caueed by !.he TV IipaI beinc
reIleded, or)'llUl'" TV's anleMIIor__~"""may be in poI&'_
diUon. Notice t'- the two iInIgM producoed by rt-ing ..., I.he _
~0C'l:In..-hen• TV aipal ill beiJw ra\ected offalllOUlltain. btdoir&
or Qther m&MIl8de atluctuft. The ......tnYeI om- o:Iitren>rc I*..ba to 1VW"
TV let MIl arrive Ita1i(ht1y difFetftll time&. RotaLe J'lUf" TV antenna to
e _ poaitJon, or m.uu & ablelded ("ulu")Jead.ln wire. Theae mHeUrH
"'"rwoI~1m. problem. I' thelle aotutioM ll1'll not dl"ed.ive,h.a,~& lie!'
vice repreaentatlve ch«k the condition~)'OUTan1.enna MIl replace bl>th
the antenna MIl ant.enna lead-In wire.
CO-CIlANNEL lNTERPERENCE
l-es!'rom two TVp~wiII-wear OIl )'OW" _ ".t-! )'OUT let
~...m-t_TVRcrI' Notethlttlletwoimae-_di(.
--'''~one piL'tllre ...beeJ:I~\lIltop~tbeGther. Codtannel
iatafeftlllle may be caueed by eitMr *'_", 'wi" ClI,lndit.... or the 100 
lion~the TV .....in rNlionehip to )"llW' Itome. PiDblaue caueed by
M ...teritNntit-Piob.bly cannot be IID1'ftted.. HowIever. -.da __
citiane..., -wJy te"...U')'. PldIima~by the locacion~yourhome
IIIIQ' be m-d or eliminated by inatallirtr •~bIply diftctionaI ....
teIn&, or~the~one to • poeitlon that t.t irnprowlI
""""""
PART 1I
INTERFERENCE TO OTHER
EQillPMENT
CHAPTER'
TEU:PHOSE8, ELECTJI:O!'o'IC ORGANS..oIIF)I RADIos.
STIlREO Ao''iD KJ-Ft EQUlPXElooT
'Mep/lonft.~(!(,IInpII1.en,~orran- and '-... ,._
...lcwfall I'ftIeh'I~rrom -':IyNdlo~Whell UliII
1IappfnI. 1M dl!ric'e impIoperty~... ndiD ...-l'llel' ........
,'. ldblll_lIterincsn r 'wellUdl_rliIft_ T1lederieelc .;.q
inlmt,E"« ahould be modiIled in)'OCll' __..hilt \l iI beirlc a/fed.ed..,.
lnwo,ft"II(e.".will eNlble tlle _ •lei~to de« lOWIll ..heft
llle inwferilw IicMI ..~J'l\lI' df\ic.o&
The dllvlce'. l"llIpOl\M will nry arft)1'di,. 10 the Interfel'll'llet~It,
ro..6anI~your eqlllpment is piddnr up tht IlJcnaI~.I>9I"byl"'O-~
I'IldIoU'aMmlt~,)'OIl IllIeIr...ill he.,. the radio opent.or'a~E~
Inu!rl'uera can _ IlR.Iing. PJPI,IInc or humminr 8OUnda.
When elecuic:aI interfH'l'net!~)'011 IbouJd uy 10 locate tht IICIlImI!
~thtInterf~f'bl\ow the dirfttionI on P'C" 10.
WARNINe
ro AVOID Mi EUY;TRJCtL SHOCK. IiU'CTHICAL OR
ELECTRONIC EQUIPMENT SHOUW ONU' BE MODIFIED
BY qUALlFIED SERVICE TECHlt11ClA/1.'S
TELEPHONES
SC''''l'toIlllWVby ndiD~call eM«J'llllI' tele;".~
~
- The U:k\pMrlll w1t'e~to\M'"
n. w' .1•• wirinr iMide Ole .......
",. II"'" i • k.-Il'
CORDLESS TELEPHONES
Dealer or manufacture,'a lervic:e
rep_tauva
SERVICE REFERRALS
CONTACT:If'YOU:
c.rdIeao~.... radio fNq......ae.. The)' .... _I,_n t_
....,. radio .)'Item$. All with any t_way ...diG, the, .re~t.o
intelfau.... from l'\o8lITby radio tnlnaDilters, indudina: otbu" neerb1 coni..
\ell telephon-. The.'CC do. not.p_conIleu tekphonel from inter.
fUU1C8.lIo_~,yoo may contact the rnanuflKturw ofthe.~r...
~If10IIr oordleu telephone callJel interl"el'Ul" l.o IKIIf\U.N\CI el 'a
eqWprnult,)'OlI mUlt. atop lIIine ituntil the intenel'Ullle;'e~minated.
Own • conll_ ILlepboo:..
WARNING
f'ekl'h-"", MI,~iJo'.nudl, JflDdi/iftJ b"IM.._"{IId,,.....
...... FCC r'eIW""/ IelepltDnere(1U'6U~.1M. rule _dcsieied to
_re tNt uhphol_1:Ilntinue to 0lIrIIPl1.;th FCC recilbatiool _
dank n. b:aI~mmpanJ' =-1 .... be wil&c to moditj )'WI'
IqI;li~LSome ..tee .1Iow tekphane coml*lite to charp for tII.iI
........,.rdka.whether)'Oll ..........ownyourWephone.
"..,intelfe_ will freq\WlflUy entel" thTOU(h the telephone itMtr. Many
_lIIllOlIeb (both puIM andtona~)indude f..t.u....en ...utl> 
_tie Nelialinl and~dialirtc. on- feaw.teI .... tFanIiItor
'ecbnoloo."" lfanIiMoriud cimlitac in __.u-~ephons......e
.... been~l.o lIIfer interfe....... p_",v.n.. Talephone interfer 
....-......IIy be elimated b, installinc filten.
n.e .tlCti,ec .fi\terinc ....,.vary KaWdin( l.o the t)'pe .telepho"e..
111_-.•filter ....lIed .. the~inIide the
_"hpitre. the b.anlhet wiD etimau the p 1blt'lll.. WodifYinc)'Wl'
, !;i .. -.;t--.i_be;~....~wn. it .. _
...""-'line l.o another l;nnd .... .-iel with beu.er interf'_ pro 
~Price 00eI1IOl n aril, inIu.... C'*l interf_ prol«tion..
See the FCC BuUetin ..ulled, 'TeIepl_lnterf_"for further ;mOl'
......
ELECTRONIC ORGANS
If J'UU"~orpn~rw:5o~inltik,t...... .... 
,......~GrJM "'-"*'''rto':
AM AND YM RADIOS
Soune.~int.trl'el"tnOl! 10 l.eleviolioJl~can alao cauaein~rference
10 AM and FM ....tio~.Rem to Part I~lhilIlwKlbook.
If your AM or~'Mntodio is reeeiving electrical interference. relocation~
the~within tlwl horne may reduoe the Interfe....Me to a tolerable IeYel.
If thia daft Mt work, klcate the elec.VicaJ deva by Ilairc the Information
beginning on~lOot thia handbooI<.
Olher interfe_ pr__ma may be muaed bJ:
- """';-w --'oa.d L'I"llal a -.b1~~aIQ' type. or
- IpW'ioua emialIiol-. fI"onI a -.b1 aIIIIUVl' or CB UWlImitter.
'not _ IiRly I*DblNi to ...........",d'6 OI'EitoMl. Wl!oea OfS"'-d
omara. it can often be CD'T'eCUd by~tilt.en or makiJw Olhft'
IIlOdiIkaUonI to the a1f«t.ed 1'I'<'tiYB'. IfIpUI'iouI .".i=r-.. are the pn> 
blem, liIt.erirw~IJIe~m,*be made. The""-,10" ab:IuId try
10 klcate thel7aMnIlt.ler~.Information about Iotatilw" tralI&rt'IitUr
opmllOl'5 begina on pllge 7 u thiJI handboo'lk.
If one nodio lltatlon can be heard at t'Nll polma QfI the dial, \he problem
may be due 10"~reIpOf15I!'~If Il can be heard on _raJ ad,i_nl
channe1l.. the problem may be due 1.0 poor~r..1edJvity. It ia
-...0)' imprvtieal or upensi"*l \.0 modit')' the~to OI'd .....'''' u.e.e
pnlblftna. Therefore, you may wiah \.0 I:OII&Idft- cbanrUc \.0 &llCItMr model
or brand~recelwel'.
WARlU,.,'G
TO AMJID AN ELECTRICAL SHOCK. ELECTRICAL OR
ELECTRONIC EQUIPlIENT SHOULD o.VU BE lIODIFIED
BY QUALIFIED SERVICE TECHNICIANS
STEREO AND HI,YI EQUIPMENT
Replace any unahielded wil"el in other equipment. IUd! u~hl-tI
a~,"",or audio ampliflel'5 witlI klrh Q1Wil)' IIhieIded wi.- Ifthia~
not reMI"" the probleftl, consult a qualified .........a tKhnldan.
21
PART ill
ADDITIONAL INFORMATION
CHAPTER 7
WH.ERE TO GKT HELP
If,..Art. fl' .lId the~C1"IIi_ in this be·d .. tan JIIUl'
W '"" po dill _tiD-. J'lIU ..., ..ant Wo _UiU _ rL lIM
_ Iia.d .,.,. for .1t«tuItiY. dutiofta. n-.~II. -mnc
~IbouL JO'oIr prDbleal that~•~llOlutiCln.
111_-.1M adch_ ked for iAtilw< and _ul-....n
....~rlll..· _10m...""" ",lI.-iJO\l.. klquiry ...lioal,..
-wn..IW.,..._
'nalo IOIdion a1.lndudeo the 1Idd.....rL FCC oIf"_lacalbu.
ASSQClAnONS
FJettroaIc IndllmiHAMoclatioa (ElA)
)b. S. Bn)Wu, E..eutiu Oi.ecl.Or rI Con.umer AlT,in, Eleetronic
ladoutrin MIodlIUon, 2001 Peruuylvani.ll AIIMue, N.W., Wuhinpon.
D.C. 20005, ...... 20214.S7-4977 m., be wntxWd lOr ...lw.- 011 Rn
............ involvllll produtW 1Nd, by manllflKturen notlilted here.
CIA ilenaae~in an onrolnr pl'OfT1'm to c1ev.lnp voluntary .tandard,
b TV 1'tICIei---, VCRI and w..dio produeu limed at~11cin1the elflClS
oIin~lh.... ofwhkh hlV'll been completed. 'nMI AIIodation I,
..im'IllwcI in an intenational pracraal to deorelo9 O'OIuntllry worio;I•
.........1$for ..mo and -tioproch.IN.
N.tlonal Electronle~nu'achln''''A-.oe:latlon (NEMAI
NDIA S....nI, p,,J:ti 'ion No. 101, "Wathodl III"_..-.1"
JlIocI. tnn- Volurp (RfV) III Hi&h-Volup~w.;_n tha
_ .... rL .......enl fII RIV in the frequenq ....flI 0.015 to 30
Wlh tI>IIl-.r bI ud wi\hhirb-~power-._IlMd..
22
tnuumiuion and dillributionIyst.emlll~liflll vo1laie. 010.6k;loyol~IU>d
IlboYL Oriilnnlly dllVllloped ;n collaboraUon with the [dillOn Electrit
InItiWIe and the RlldlllManuflld.u~Aa.lclalion (now the E\ecttonlc
IndUlltrie:l Auociatioro 'NEMA PIlblicaticn 107 .... .me. beenadop~
InU! the apecil'iulionl or varioua utilitiel and lovemlM<lt.~cies,
jllCllidinc the Runl E\ertrirICDUon Admlnllttllllon. for additioPal inrOf'
....tioa write NEMA. 2101 L Sll-eet, N.W., Washinrtlln, D.C. 20037.
AHen Org... Compe.ny
When 1\ complaintia received via 1\ de*r, Allen Orpn Company aendJ:
the deale, an informllti(ln.llervice bulletin on RFI and autrlcientcompo 
n«lta to cover all amp!jrlf-... in the .ffect.ed ilUtnlmomL "'11 ..,rv;a, hi
offered at no toSt '" the l;\Ut(IlIIU. Refer R1'1 problems to the 1000l Allen
dealv. Inqui...... may blIlT'1Dlk to Nllt>annl Servia! Mal\aCet,M~.
PA 18062, tel.21~9li&-22QD.
A1tee Lan.'ng Inlern8tionnl
Refer.n Rt'! problem. 10 All.ec CUll.omer Servicll DepartmenL Contact
Alte<lLllnainClnt.emat;lInlll, 10500 Wen Reno, Oklahoma Cily. OK
73127 or P.O. BoJc 26105. Oklahorna Ci\1. OK 131.26. tel..~I1.
Arne.iean Organ ParU
RPI complaintl related 10 Thoma. Oqro,. may be.en! to Mr. Daniel E.
lIorer, American Of'iJlll Paru. P.O. BoJc lUG, MortonOrov~.tLGOllM,
t.eI.708-2!l7-M!19.
23
Apple Computer, Inc.
AppM prod...c:t.I include bul.iMu, proreuional, ed......tional Identil\c,
inclUltrial and home coml"'tftW, peripheral devKU. and 1OIlwan."" 
prodlJc:t.l a..dwelled to be compliant with lhe rcc~linMcoYe'rinc
CI.- A and a- B oon.I"'_ ,.wiceL Illql,Iiries~atedto RfI tl>ould
beadd~to any oflKl' moft Lhan 800 dealeroOpel"tted t..r..l One __
............ten. Ir u.. oervice leChnirian. u-e...1lNIble to .tv.tha am..
IU", the,. will UN1ta« tll" Corporate En(ineerinc s......iceI Group.
ItIqIliria ....,. bIl ...~to Apple Compute., Inc. 20625 MarianiA~
Cupertino, CA 96/)14, mail.cop 26A. .... can 800-776-2323,
eu-- prWIe.... inwolvH>c RfI .bnuId be nfwnc! to GenlI Knou,
Manq8', Enci_rinc Support Group, 1531 131h 5l., Col...~,IN
47201, tel. 812-378-1304.
Audio RelIean:h eorponllion
"""dio~rd>mllll...fllCt>J._ hi&h-.end IWffIOequipmen~and ..lat.ed
prodo.>cU. Itn ....pp.euion ;. inoorponlted in lhe deJicn or tha prod...a.. If
a Q.lItome. ihould tIllXlWlIAl. an Rn problem, ,.,.,\.ItCllM nearut Audio
Re....reh Deale. or contact CultOn'e. Servica Daparlmenl, A...dio
Reaeard> Corp., :\740 Gree" Circle Dr., Minnetonke, MN M30t3, tel. 612·
939-0000.
Baldwin Plano Ind Organ Company
Rn oomplalntl ,... lI.lIlIlly renld to the 10Cll1 Baldwin Dealer or
Service Ted>nician. f'aetory pe nnel are available to aain the local
Technician if" necesaary. $evenl Baldwin Technieal matlllDl .upplemlO'lta
... available with inUNction. for RFI suppreaion on .pec;m modela.
Thia in(ormation ia available upon~Inquiriea m&1 be dir«:ted to
the Manqer, Orpn Technial Service, Baldwin Piano 4'ld Orpn Co.,
1101 S. 8eedlwood, F.yeuevile, Aft 72701. tel50I..43-1311.
24
c.rwr Corporation, Inc.
c.rvu Corpor1Ition IIW'Iwactures hieh fidelity componenta. f'rob&em.
pertit.inirl( to RFI eould be directed to 20121 - o&8th Avon.... West,
L,ynnwood. WA 98036, toel.200-77~1202.
Chryaler M01(ml COrpo....t1011
Qullltionl roncemlll( lhe eleottromal"etic Q)mpalibllil)' orCh~ll1T
McM.lIl'S "ebiclet -"oIId be dilCUSMd with )'our vehicle dealer Dr may be
.dd.etHd to th" CII.,.le. Moton Zon, OffIce lilted in the O....el'S
Man....l.
Crown International
Cl1lwn Internalionll! i. the manufacture. or hirh.end audio pr«!u(1l.
Rn IUPllre8lliorl II im:ol'1JOf'llt.ed ;n the dHi(n of the producL If. eut 
tomer ahDUld encounter In ftFl problem, COIlta(l !he Technical~
Department 0(Crown Inum.tional, 1718 W. Milha",.ka Rd., Elkhart,
IN46517, tel219·294.a200.
Curti. Mathe.
Cu.n.i. MathM prod.,," indude color 'I'Va and ltef'flOll in portable, con 
1101. and combination confieuraliOllI. C...lOma. complain'" lnvolvinc
RF1 should fint be I'MOlved M \he ....il-duler left!. If not ...tdfoed,
then the complaint aho...ld be mad. in writilll to to the Conl,.."er
Relations Department civil\(.n delllil. 0( the problem, Ilona with the
modellnf=tion, aerialnu~.date 01'11110,~.ler..,d...rvice hisu..
ry. Ead> compla;nl will be handled ;ndividUllUy. Write te Curtis Mathe.
Manufllcturinll: Co.• Con.umer Relations Oivision, 14:;1) Flat.ereek Rd.,
Athena, TX 75751, tel. 800-473.1920.
~leoElectronic.. A subsidiary of GM Corpomtion (_GM Corp.)
CUltoJller. JIl'y refer RFI inquiri.. rellted to Emenoll Radio
Corporatioa, tvInd ndio prOOIems to Mr.AI~.E...- Rodia
..._ ..pply 1I!teo'a. n.e.ld..... io; E......... Radio Co.porstion, One
Em _ LoDe, North BeFzon, NJ 07CWo7; tel 201-&t tllOO.
Epic\u'eProd~fOl"llJ"'rly E1pa. Marltetin,.llKIu.mn, I nc.
CompWnti ... hond'led with~peclto partl Ind labor on anindi~
v.rJ bui•. Neoeuary modilicstionl for m ...mode on. no-chorp bui.
for jIOrtI .nd Iobor durine: the wm III inlltnunent w.mwl.1. Beyond wa....
""1.1, modirl<\&t.ion partlore nvoilllble free ord>1I~n.e cu.tomer then
PllJII for lobor ;nwlved in the ;nllan.tion of plll'ta. R..rer RFI probleml to
Mr. Jim OnnNl, National Service Manllpr, 25 Hille Sr., Newburyport,.
MA 01960. tel. 800-225-7932.
I' Ilny RFI probleml are encountered with uni"" in the Fannlln
Courier pl"Oduct line, indirid...b Ihould write lt81l Myford Rd., TIIItin,
CA 92680, ortlln 714-&i9-9890.
F'"1Sher <:otpo..tion~SFS Corpo..tioa)
~.-..JEJeetrie <See Thompson CanIumer EIectrMa, Inc.)
~....l MotonCoo.-ation
F..- lime to Ii.... yuu may N1ve qullltionl conceminl thI eIectromIof 
Det.ic: compatibility of mobile tranlmitten when installed on General
Mocon vehiclea. To help .void ..d- queltionl from .risin&. it ill urpd
!hat can blo WI.. to follow any oppIicable GM RrYice p..-:lu.... n.e
1DcaI GM Servicll MaJ\ll&u for the Car or1'ruck Division whole vehicle i.
inVlllvad ahO\lld be contac\.ed for infONnlltion .IIbout ..d> teniI:e p..-.
du.... Ir)'Ol.l Ire WUlble to obtain IUd! a'liltanoe Ioeally or if queltionl
~rthelO!'Uarise, OM has establish!!d a C«Itl'ltl contact point ror aliluth
25
26
inqu;r;u.AccoTdin~I)'.YO\l should dirtU your inql,li.;el 1.(1: Cenaral
Moton Provine Gro.md, EMC Department SuOdinr 40, Mitronl, Ml
<t8Oot2.2001. leI. 313·685·5200. That deputmtM VIm direct you'
inquine. lOth. appropriate division or llAlr wilhin eM and follow up
1.(1 _th.~appropriate act.ion is taken,
H,H. Scott, Inc.
"'1, manufacturer off.n I .imple Inllt\lrnent sheellO.kl cwtome..
in reIOlvinr problem. invol";nc RF pickup. The infonnauon ine1uds
luuaUo". .boulouiltlble equipment f'OWldill(, power-liN bypusinc
and hinl.l and Iup:ettionl on how 1.(1 deu!nuine whe.. RF iI; I!l1terill(l
the equipment. C...nomen Ihould rer•• any RFI problems to Grell'
elordano,Eniln~r;nlnoporlment,llGOI Wutside Avenue, North
BertM, NJ 07047.
HarmaDl'Kardon,lne.
RFI proble...........1d hi direa.ed 1.(1H"m.~rUo.nat 240Crouwly.
P••k Wilt. Woodbury. NY 11797, tel. 516-496·3'06. Anention:
Cuttomer Relations Dept.
Heath Company
Ileath Company iUUeJU W\., fOf"f.~Ie'rVite on ....\U.. ntl,1.e<l1D
RFI, reprdless ohhe p'lldlla. line involved, eIlSUlnlerl may now re6dI
the Tedmical CoollltUilion Department by either ",,"lin, dil'Klly to
thP~depPrlmerll Pt Ilea.Ul Company. BentoJ1 Hprbor, Ml~0022,or by
IIlina: • new direct-line telephone Iyltem to the department 616-982_
3672. Do not write to an Individual.
Rltachi Saln Corpo...Uon ofAmerica
HitachI', primary prodllcU TVI, ...da, tape renlrdera. 1Ii·1l CGID·
ponenu end video U1pe recorde Hitaehl Solei CorpoMll!on r1f America
ettempta to cur. oath JU'1 problem 00 .n indivldu.1 buiL Oll'tome...
d>ollid provide model nlln>ber and inrormation _mine thenp~lIrer1f
the preble",. lUll problems Ihould be refel'ftd to the n....t lIit.achi
Recional Servk.t 0ff1C&. EaltUIl RqiOllt;lI Offit:fl. 1290 W.ll St. W..t,
L,ndh"..&, NJ 07011, lei 201.9$8980. AtUnlion: Service Dept.
Irrdwulern~Ifl-IOffb, 1400 Mo1'H Ave.. Ell< Grove Villqe, IL
60007. AWIltion: Serrict Depl.~'ftWft~Q'Jb. 401 W.~
Ilhd.. Compton, CA 90220, tel31t).531-8383, Auention: Servi<:e~
SOUtM....&~0ffI«. 5120 Plaza Dr., Collec_ p"rt!. GA 30349,
Attomtian: Senice DepI.
.I.e. Penfte)' eo.....n)', IDe.
.I.e. Palney Company ..... that l.\lSlDIMn with Rfl ..\iIleua 0IlIltacs.
th••.-..., J.C. Penney stlIre for peTSOnal aMiltaI>ee, "I.e. Penney
Cumpan,..Inc., P.O. Do>: G:;9OO, Dallas, TX7~,tel. 214...591-3500.
JVC
JVC Company ofAme"'=n requesUIthat~.. with RFI problem.
CCIlIUa, JVC ew"'rmo. R2lationl Department at 107 UltJe Fall. Road.
Fairfield, NJ 0700., tel. 201· 79<1-S900.
Ken...-ood U.s.A. Corp.
Kalwood I"IIqUeIU that consumen e.periencinc R,F.ln~~pralr
leml conUlat the CUltomer Relation. Department at 310·639·9000
(California). Rn mllJl\l.I. "vine idelu, p<>SSible 1ll1ul.lonilUld actual_
hiltori.... Drfl Iyoilllblellll>O dla'1:fl to consumers.
Lowrey Division ofNorlin MUllic.lnc.
t.>wny euatomerllhould refer RFI problems to th,loo;pl 1.0""",, deale.
or eertified Lo""l'e)' t«:hnirian. Lowrey J'"Ioo"..n techniciant with tech 
niaoI lite........ repnlin& RFllllId will provide aulltanee to \oaI1 HMeI
arpnizat.iol\l lhrouch Its IUIIf of field 1.ed>.nUI .ep'"t11ullv.. when
n-kd inqIUrin II:I.IlY bed;~to Mr. Larry R. Thornu, D1rectllr III
PToductSer.;';',107 LauCook Rd.,DeerfieklILGOOI~
Madrit:al
Add..... inquiries Ul lh. Madripl Audio LabortUlries, Inc. AtLn.:
Tee:hnkal $flnioM~~P.O. Boo: 181,Middletown,cr~1.
~\"O"(8M Philipa CanIWDft" EIecuunio:I~
27
28
Mllnl.nt&Compun)', Inc.
Marantz manufaduretl AMlf'M ._iven, wnen, amp'ir.....,l.f,~
I'I'lDDf1leq, ..-u p\ayf!n and audio IYllemL In the event Iftpecial fRJ
_ reI"ltina: from extrl!lIlely hiEh fielda, <:UlUtct theTedut~lServlca
Dept aL Marantz o;Il'JI',Iral.e office.. Modirleationa _ ..". 1.0 ",lGlvl
auch Rn problem. Uti provided lei NIUlme.... on an inc!i'i\duaJ bem.
Man.nu ComllMY. Inc., 20625 Nordho/fSt., ChattwoM, CA 9131 t
Mllt.u.hi... EleetTi. Corp<)rIItlon of Amerlc. (5.1 Panuonl"
Company, 1'edmie. and QuUllr CompWIyJ
Mc1ntoe:h Lab(lnllory, Inc.
Mdnu.h hal. nllmber ofauthorized lM!n1ee -.eencies \ocaled throuah·
out. the country. e-n-will be llUilUd toreeei~prompl. help. RFl
and other oervlCI·relal.ed problem_ Un be dirKled to Mr. Michul
S~c:er,C.utomer ServiceMan~r,2 Chlmben St, Binalur.mt.on. NY
13903, \.II. 607-723-3512.
Mld~ndInternational Corporation
If ..., RFIprob~are (lIlCOWltered with Midland pClrtllble black·llld·
whlta and coIorTVa or audio and ....dio producu, individual. Mould COl·
tact. Mike Bland,C"'ID~rSem.:. MAn..,.••, P.O. Box 1903, Kan..
~,MO64141, or at 1690 N. Toppin«, KansaI City, MO 64120, tel81&.
241-8500.
Mitliubiahi Eklrtrlc SalettAmericlln, Inc.
RFI~(tOm lbe fIeld, beytnd the dtiller', c:apab;lil,y to resolvto and
in which Mit.-I,lbi.hi becomn involved, II"' handled on an individuol
!>QiL All at.tempU will be; made to eiva tu,lIl.lJ<Mr S!ltisfld.ion. Mitaubilh1
~c.ha~requeIU for aNi__be; addreued to c.:...w_r Relollon.
~partm~t,11157 P1lWl Drive, CypnlllS, CA 9063Q.0D07,~I.71.4~22Q.
14&1.
I'tlontlOmvy Ward
SeTVioIl for RFI 1h000Id bI obtalnad from lha naarllil Montaomery Wlrd
10000lion. Ir lleTVlee il not aVDllnbla loenlly, tha a.ltomer mlY write to:
Cwtomer~Pnldua t.I$lIlIpr, Corponlteomoe, On, r.lonte\lmel)'
•
Ward Plua,~.Chial2O. U. 60671, tel. 312-467·2814. 'nIe Monll'Omery
Wanll>eld~orpnization can call upon (..:tory and aJI1lO...t6 MCi·
~u.1en~for.~in handline difficult RFl problema.
Mone EIeI:tnI Prod...n. Coo poe atio" (See Plk>l. Audio SyIUmIl
NuT_.lnc.
Refl!< Rfl problt.... to Mr. Dan Ledford, field Senice W• ...,e••
N.n--,~MIId~lind Red Bank RdL. CincinNoti,OH~.tel 1 
800-9'l2-2:i91
()dysiIey (See Ph.",Can_Elecuonial Co<pJ
PlInuollic Compllny(Mau.a.hita E'-ric:Coo,xntion (J/ Ammca)
When In--.<I RFl occur, the~Ihou'd tIlII1t.aa. Mabwhit.l
Se••"-Company (MSCI. the oenice ann rw~iee-.c-ny. BoO>
companiee ...dl~illOO.1JlMnw.shila E:1«lric Company of AmHica.
loquin. ohould be ....t \.0 MSC.50 Meadowland Par\""ll1. B.ta-.s, NJ
07094. AU.ention; Con.....- Main Depa..-.m 2F-3. tel. 201-348-9090.
Thflcust.omer ihoukl provide InOlIel no.unber, otriIol number and inf""",,,
lion concen,i..... the intenete",,". upon~ie... of the prolJll,m, the rol"
tomer will be c:ontaCl.ed in an attempt til T'fIIOlv. the itlterfe_ problem.
Ph1Ul8 Llnelt. Coq>onltion {Division of Int.emBtional Jenllell, Inc.)
RfI proble'". ohou\d be directl!d 1.0 Phil. Unear Sel'\'ke Ikpt.., AWl:
John Lo-tl'Olcio. Di., 0I'5111eo, 4136 N. United I'lr.wy., Schiller Park, U.
60176, tel. 8OQ.323·0221.
Phllco(SeeI'tlil;~Conillmn ElectrOde. Corp"
PhiliPi Coll$Umer Ele<:trOoi<:s Corp.
Refer ndio frequency interfe...nce complaints too; Conilime. Aff.i..
Department, I'tUI'PlI Consumer Ele<:lJorIieI Corp.. P.O. BDx SM, Jtffenon
Citr. TN:m60.
29
30
Pilot Audio S)'Sl.el1lll
RFI~on,plpint.srell1~lJdto Mo ...e and Pilot audill prOOliCti may be
referr6<110 Mr. JerTy Ghanem, Director of Se ...... ir.o'P•.,. Departmlllll,
11340 Shennan Way, Sun Valkly, ell. 91$2-
Pioneer I!lce:tronle.
Contact Man&£er. Cuttomer Servies I)e.ptlrtment, Pion-' Elearpnif:ll
SeMce, Inc.., Box 1160. LOlli 1Jt,ach. ell. 90801. Upon I'8O!Ipl II lnfonnlll 
lion OOO'l;:Orn;nt RFI prcbleml, the Man.,.,. will fo....ard the received
jnfonnation to Ihe~rperwn within the. IIlmJllWly who tan bullw!lp
reoIve the spe<if'w: Il'd*m. Plor-.- b-and uudicMdeo prodllCU, indud·
ina: I.Atoer dill: playel"l, are distnbuteel by PIoneer Electronief; (USA), Inc...
Lona: Buth, CA. The pointof'contact, nboV'&,"'rves both o:crmpanin.
Qu"",. Company (MlIlll..,hita Elect.rieCorpomlion ot America)
WIlen~ot Rtl _T, W --.-ahould can\Al:l. MatauhlUl
5e.....Company(MSC~the HrYioe ann 0( the QunJat Company. Both
companlel ..e divialon. of Matsushita Electric ComPfl.ny ofAm~ica.
Inqulliel mould be 'IeIt to MSC. 50 Mtadowland Ptlrkwll,Y, SecaUollWl, NJ
01004. Attention; ConlUmer AffoirsD~rtn1<I'nt21'-3, 141201-346-9090.
Tbe CUllOm« IhDuId provide model number,.erial n......tler and infonn.l·
tion coo>c:eminc the int.er1"trtoel'. upon T1!'iioew ofthe problem, the a..aneT
win be"'"'1.IIotUd in an luempl to resolW! the interl"eotl'lCe problem.
RCA{See 'J'h,omt<lfl Con.lIme. Ele<vonic:.. lrw:.l
Radio Shack n'andy)
CuJtomen who meow,t« WlKrue interlerella problell\l involYinc Radio
Sh.~k....diop'od"'~I.m.y ... ,it. 10 M,. R.ndy !.th,. P,od... ct
Dev~lopmentEna'inee,. Nptional"~lIdljwU'l.en,1100QneTandy Cente"
Fort Worth, 1':< 76102, tel. 817.g'78-68W.
RFI pnlbIemJI involYina: the Rodien Ot-pn lOlly be NfKnld l<l Ridlard
(Dick) JoNuon, Tedu1lcal Semce Deportment.. lSOO N.t. 25th Avl!l'l\le,
HillMloT'O, OR971~,tel. (003) 643-4181.
Hotel ofAmerica, Inc.
Stereo •.e'b".....,Jifoen, tw>Ms, ..d 1apI!decU.~mad. b7 Rol.el
Rf1 ..ubk.... sbouldbe r'ff...... to NwamolSe.via~,P.O. Bent
653. ewr.Jo, NY 142.40, tel 716-842-18O'l. RFI .......... will be h....n..d
~incto the _olO\lrlimited WIIiTUlty.
SFS Corpo....tiQ,n
Ihn RI'I problem OlX\In on. Sonya or f'isher product., contact the nenr·
..authorized SF'S .""ice deDler. Should the problem peniS\., either the
....lItOn"'r Or the .uthorited lervice dealer may contact src Corpon!.ion,
1200Walnu~Street, P.O. Box 9038, Compton, CA 90224, Attention
f'.ncineeoinll' Department, tel. 31ll-M7-5830.
s.-on(Electronic,.:
When irLaMIcn olRFI oa:u.r, the tcnlllU1W!!rlhould eont.a the TechnO!
A •'anoe~at1~16,11-.lDOdeIand..,rWl1WIIbn"
efthe.tr~prod..... mua be IlIPPhed IltId if penNa, • ...-ion on
Ibo __olthe inlaf--.
Rf1~will be handled ..,..,rdinc 1.0 the IermIIIl OUr limited war·
...lJ'. Filter alllUnd inJUn.tim wrteS.re the_r'. retpONibili.
".
Sanaul ):Jectron iclI CoI1IOO'lllion
Rfl problems should be diretted \.0 Sllnsul EleclrOnic., 17150 South
A....u,., P.O. <1.687, Cor30n, CA 00746, tel 31C}.G<W·7300, AI.IJl: Nat.lonal
SoleD Mllnlli'!r.
Sanyo (See Sf'S Corporution>
Sc:ieotiroe Audio E1«tnHlka, Ille.
!War RFI ......ins 10 Mr. e-.e NijaIn, National Sen..... MMlICft',
lS02Gace~MootebelD, CA 90640, tel. 213-726-9999.
Sean Roebucll ..... Com..ny
Saat1 ..... lhat _ .. with RF1 po-obleons ;nvolvinl • Sea.. prodl'l1.
"",,!.act the neareJt Sean IefVice~anmenl(or hli.lance. lnqui.....
~be directed to Sen.. Tower, Dept. 702850. Tech. MIlT., Div. 57, BSC,
39-9.96-1}1 Chimco. IL 60084, tel. 701l-2lI6-2087.
31
32
Sharp Electron;';' Cvrporation
RFI prOOlemi invoMlll Sharp produetl ohould be menecj to lhe nearell.
Sharp AuthoriudSe~Station (SASS). To obtain the .,jd.- IlJIdIor
"Iephone number or the nellrelt SASS, pIlaU cnI11·8oo·447.47oo.
$hClO,lId thIl problem pen;...~t.ber"'lUItntr or SASS may Dl)nlact Sharp
Electronic. Corporation, Service and ParUDl~l.ion,Sharp Piau,
Mahwah, NJ 07430, Attention: Customer Infonnation Center.
Sherwo«lllnkel Corpontion mMufllCWlft lterM c:omponenu, .}'$«'....
and Clr Itereo product•. RFI p.oblema will be bondled a(:«lrdfnt 1.0
Sherwood', Umlted Wnrrllnt)' pl'(l2Tflrn.Ple~oonl.llet OUr TechniCAl
RepreMfltatiVfl. 1384:1 Artelia Blvd" Cerri\.Of., CA 90701, tel. 311).926 
6337.
Shurenrothe~.Inc.
The manurK\1.lrerrecom~.w useofbolMotd·tin.e. low impedMal
mlcrophonel and CllbleI. Ifan RrJ problem~N.n« u.. &bowt mM·
w_ he... bftn Ulken. the ....1O....... 1h0ll1d contllCl Shure Brothe..... Inc.
with rpeciliCi *' thot they mny be able to help to/ve the prOOlem. Role.
Rfl proble.... \.0 Cwtomer Servica Dept.. 222 Hartrey Ave., Evanlll.Oll,
IL60'202,~.708-8966-2553.
Sony Corponllion ofAmerica
Son,. CorpoTlltlon ofAmerial requeIU RrJ inquiri.,. be direettd to the
Sony Informetlon Center, Sony ServiN Complny, Sony Drive, Park
~,NJ07~,tel. 201·368·9ZT.!.
Sound ConC4'ptt
All RFI romplolnta Ill'll handled.~the IlWlilIloborIIllIriet:1I~21N~U
Rd•• Brooklin•• MA 02146. tel.617~llo.'Ill, offeodlna: Wlit Ihould
ba IleCIIlmpanled by II deacrlption 0/' lhe nature of lhe RFI. There I. no
dlarre fo, thl. aervloe except for return .hipmenl.
Soundl!.lgn Corponotlon
Soun~Corp.Aalo.JtJ~l)ynamica rfque6U lhat 1111 !leN;';'. prd.>lemJ
reltlti"& III '*'lleIW men:handi.... bIl refened III Mr. TIlomu R. Creene,
Admini.trlltIY' Vke Prelident, 34 Exchanae PI., Jerley City, NJ
07302. till. 201-t34-10Ml. All ...rvice probl.eml onIl.erv~;.eare to
be ...rerred to OIIr aulhoriud te ice __I.e .... Th. nearftl _ can be
b.md by callinc toll f1'lle in the tinental U.s., 800-631-309'l.
Sylvanilo (SeePh~lipleo mer E1oec:tronics Corp.)
TludtKo:....atAmeric:lI, IDC.
When RFl oco:un In Tandbel'l prodIlcu, the .....,uflktunr.....that
the unit be ,."wmed to \hem. ,.."..",... will do an,. .nodifiation p jble
to etiminale the RFI. Autlwriutiun should be ctuined from Mr. Sl.e¥io
~prior to return ofthe unit. Mr. Kmn B.,.,., PI Mident, 122
Dupont St., Plalnview.!'>'Y 11/lll3.1e1.51~7o.
Ted>nk:l (ll1ateushlta Electric CorponlUoO aIAmerlClll
When inItan_ fi RFl CICnIr, the customI!r ahould ClCll\uw:tMa~ta
Sef<ioN C""P"''11 (MSCl, the lel"lice ann for Tedv>ils, Both DClffipaNes
.... divipo of Mauushitll Electric Company 0( America. lnQl.liri..
should be t to MSC, 50 Meadowlnnd P."'WlI)'. See.l.IC\1I, NJ 07Q9.t.
Auenlion: eon..mar Alfllin Department 2F-3. leI. 201-$48·9000. The
alItOmer should provide lI>I>Clf,l number, lerial number nnd infonnlltion
toPceminc the ;nt/lrl'el1'''<e, upon review or the problem, the NltOmer
will be c:onlllctf!d in lin Mletnpt to~l\'ethe interfertnce prdllem.
Thomllll lntcrnntionnl Electronic Orgllna (See AmeriCilII Orran
PaTtI)
ThomllOn Connlmcr EI"Ctronic$, Inc.
Rn problem. inY<llvincTV, VCR ",,01 "udio producu IIln)' be~ert'!Jdto
LlI~ceElkin, Coordinotor, Conwmer~IDtion,.Thoml(ltl Consumer
Electronks, Ine., P.O. Boll" 1976.lndiannpolil, IN 46206, I.e!. 317·231.
41.5 t. RequtIt.I rln" lilten Ihould include model R\lfIIber .,l(l if:n/ll num·
bIo. at the prDducu involved.Fil~.;llWIllation dul'll'l will be the CIlS 
_'Iresponsibility,
Tadlibal Aiiot'!ea. eo.....mer PI"o.hu:U.lnc.
o..tonotn Ihould UlntllCt the nearest Zone 011'""", IiIc.ed below to obtain
........- in IOMnc Rf1~invoIYinc Taahilil .udiafoo ideo PrOd 
littL M•. M. Pluchino, EaNm Zone~),~.82T~ltoDd.
33
34
Wilfnt. NJ 07470. tel. 201~8000 Mr. R.~Central Zone 58 •ice
Manaler, 1010 JohlUOu on.., B"rr.lo Gl'1I'n!, IL 60089....1.
312-641-&400.)k A.~WIIItenl z.-s..u Me'pr; 19600
Sau&h \buliWl1 ...--..,"I'brrance, CA 906Q2, WI. 21$-770-3300.
Uaiden Cor'pcJrtlUoQ 01 A-.ka
Unidm...thIl RJ'l pi ....,.iIMlIYia(thtUproduNbe I , .ed~
Vaiden Qp I 50s fie» and Pwt.. 9900 l/"Irpoint om.. &.o.iIe 134,
India".. )I.. LN <46205, 18. 317--842-2481
U.s..I\'C~(See JVC)
U,S,Pk!~r~CcJrpontSon{SMf'Io-If)
RFI p,...... IboWd be oOh t toV~0 __S..iIa!,
13701Wl.V-=" c.."""""l,CA96OO8,' 1 jhxttOll 85s&1OO.WewiU
cIoGW" \IlmOlIl to .two.... the (I-wm-\pi ....'.Iotbeir.i f ....
~-.canl.ller~Ccwp(ntSoe
Wel~ia. pri....1llbeI manufletwwg~mer~
Inquln. related 10 RIo' Jhou}d. be Iebled 10 the pri....1.I.bft~
(diaribulor) 'A'tloIle~~OIl. the model.1tiIllber label ...txhed.
10 the~"\>eri'l poi:JkorM which Il1I\Y be enaJWllered by prj.....
label C\Ml.omIenI(m.tribu~are llIIU.a1ly Ieis: .ed 10~1.Gudner,MJ:
Ham McComb. Senlat Manqoor, 27'01 N. Klklare "'...... CtUatco. n.
00639. tel. 312-262-823).
Wbltlpool. Corpontloo
RJo1 compIai.ntI rNud to oldern-.....m-.v be~lloMr..
o.nieI~StUD~n-Produde, 100 1"101'_ Rd..
UImbud, 0.60148, tel 800-323-4301.
W.,uber e-pe'Q'
'"" Wuriiber Comptny mabs -.il-... toll,,*, ttlephoue line,
~2930.Io.....~t.eduUcianorC".....ill Ul1 wall~
pertalnirclo Wurlitaw ............ 'I'I:lI! WW'litaM' C ,_., _i...•
I
....
IItafl'mrltkl tervice~who can ....~'" RFI problem
ari8e. John L 'IbuaIirc.~Cons"ll'« and Marketilli Servicea,
Wurlitaer Co., 4103 E. Gurler Rd., 0eKalb, 11.60015.
YAMAHA home and car aJdio and video prochxt CXIMUlnen wbo
lIltperito_ nodiorNq~1XJ'in~rellftare invited Lo~
I.a»-4YAMAHA.en.6097,llI'writeIOtheYAMAHA~O:rp,
USA, AU: 0 ......~67220nmg!ettJ0rpeAve.,Buena Pwk,CA
90620, __'ll'«JlI"ll(b:t iDbll pejo.,
35
36
FCC OFFICE ADI}RESSES
eM ...... _
__ 0
........,
------,
_.........
_0 .
---
----.".-
----
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_= 0
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-
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• .0....
--_.
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........_..... 
..._--..__....,
_"'D~.
._~-­
'_0 ',C
_.-._,--
----
"-...,_....
-"..-
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_C "" 0
'.0"'_
......._-......-
- ....-...
""" _K._ v_ ,_
"_C • .-_
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_......... ""' ..,......
_11'''_
""o:c:ooo, ......... _
_ C 0
n _
, -
-- 
_......,..
.-..............._ 
r-O .....
_........_- 
-_.-._,
--
...-....-.---
"_0 e
..' -
- ----,
---
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........." 0
_..... -,..
---
--'-
-- 
,-"  
.--...-- ,-_.-
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--- 
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_lItIl_'"
..." ....._ 
'_C 0_....._~
.,__._...0&<>fII
_,_,." n
.......""' ,....-.-._c .._0--_
lI:IIIr.-........
"""-.._-
..... ..- -
......."" ,_...,-
.........,,-__e
"~.,_...
_..
..._._- 
_......,.-
37
38
CIIAI'TER II
FILTER INt'ORMATION
The folJowing t.abJ(, hAs been _rpted from "Field Re8O\ll'C(!1 Oirectory",
1985 EditKln. American RadioRel~League (ARRL), Newington. Om.
necticut 06111. It is reprinted ...ith their pennisllion.
The table is ba..oo on the resull.il of ARRL telltll eonducted on the mtel'8
\i8tood. Newr~te"'llJ\!introduced into themar~elldI year, and othe'"
are dillOOntinued. Although ARRL tried to make l.heIe telltll IIlI oomplete
IIlI polllllble llOllle available llll.erll may J1Ql berelll'elle~.Some <:J. the lUte",
liated ....-y TIl) longer be available.
.............. "".....,
•
•
•
"
•
••
,
u
..
AI.__ (dlli
llO.~r'I".'10 ....1" M'l>
t<.1I) ITVI
In><·r.~_~IGH':H.
B~TrERHY.T'Tt:H
'....151)1'10
(HAXl
1-O\fl"r.R _
.>:rrt:a
=
"' "'
CIfl'VH
,
"'
II 11I'-3700
•• •••
t;,Q1H .. ..
fntorlll,.,
0'
M
TV4.'JJO LP
•••
..
TV42LP .. ..
"..,.."
0'
"
H.......
",...
- -
,-
" "
.'R<II-7S
"
•
=
•
"(""'1~·2
•
&
EMI·TV75
• •
TWI5-HP
"
•
,
."~
,
~
,
~~
,
0-.'
,
"'""-
M.....
,
J,W.)l~",
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10101 __
,..__"..11__
CHAPTER,
TECHNICAL INFORMATION ."OR SERVICE
TECH.~IClANS
THIS SECTIO,V OF THE HANDBOOK ISINT~'DE/)FOR USE BY
TV AND RAIJIO SERVICE TEC/lN1CIAl'-S. IT IS I't'OT INTE/'t'DED
FOR USE BY THE GENERAL PUBLIC 1'0 AmID ELECTRIC
SHOCKS, ALL MODIFICATIO....S 10 ELECTRICAL OR ELEC 
TRONIC lX/UIPMENTSHOULD BE PERFORMED BYQUAl.JPIED
SERVICE TECHNICIA."''$..
n.- chapter c:ontainI thfte~SMion _ irMllvH ndio traftImit 
I«modiIIeMioIw. Sectioa \_pO'idos ir6rmation.oo.n moclityirw~
l!IianI. Se«lol'l thfte~iDIllnrwiDn.tlau\ how Ull'ftOlve f'M,~w.
lricaI and" inlek.u..... pnlb1en&
1\ would bebelP'ullCthe~,ouare NMilItirc obtai..the~
of the tBlwnil.uor opentor Dr~~'nUl moperltion "ill
eDlIble ,ou UI det.ennlne if JOIlI" modifieationl are effflCt.iYll.
SECTION ONE
RADIO TRANSMITTER MODIFICATIONS
Ir)'VII are l.ry\ng to ""Idify • nodio t1wI$mitt.er that itcallains interferelK)l!
\.ll t.e1evWon re<:eption, )'OIl .bould detennine the rolJowtng:
I I. the t..."srnitt.er properly grounded! The tranlmitter abwId be
eonrM!<'ted 1.0 • rood eartlI il'OOOO with. IaJ1'l diameter "m or
oopper Rrap. ThIa will Mlp~interfere....... r.nd !.he hazard of
eled.rictJ Mock 01' lightnil'lll' lIaJnage. Wide IU'apM have mudllow\>r
impedarooe to Rt'~nergythan round ....u- A lIirJrle pieol'e of wire
connected 10 • JTOUrId rod may be an open cim.l1t. if iU length is
.-.mant at !.he ndio &equency.
% An! hannonio:II orIIp.Irio:u~p _.It? H1O,,ou Mhould auempc.
Ul delennlne ...hether they are radi8ting from \ht:.
-
-tniW'· . "I 1ine
41
42
• I"int. Jll- • kJw.patl5 rIlter ill lM antenna (eedline, or in
u.e~linll to the __I~It )'011 _~an
__tnrwniI.t« 'lritJl • Iinev~.tIdIed. inIl.aJl •
tIIur between Ole uw.nilter ladter! and t.he Ni~''''iIlpul..
InMaII • -.d tIIur .. the aonplll~U.~I.lNEAR
AMPLlPlERS CANsar LECALLY BE USED IN THE CB
RADIO SERVICE.
~Nst. IICIcI • line llMr to Ule ...-alnl in 1M AC 0UlJe(.
~'"""'....... ,...~.. <lDI'd ,.&c ...me w M -ac:
1Il0¥e, t.'" or IDop lM~<'OI'd... plMoe )'OW'
hand ••..nou. pllICft alone lhe eoni. <:Jt., re (or '-'e _ c ..
elIeot-n'tJthe~"'TV ilUPf<m!nee ."I\ile)'OU ...dolne lhi&
There ..-ill pt'llt.bIy be IIUbM&ntiaI~in Ule inwff,rellce
~if' the Jll"OI*m ill cauIed by ......alnl .............
III M...... thol~.... ,.~RF -ov IewI.
~onthe t:XUrioroi the eou......~·. -, line
HWhR~'~IllII1 beeat.-lbJ. poorty~-1)'lIl.em
or. b.-lr. In the ...tenna', lrSnImillion line.
c Mab aun! that all lead"en~ri"lClheIl'lll\llTlit~rrahInet lin'
adeqllll~lyfil1A!M. Any tnnamItU!r wllJl lIII1Iltel"lld leadl ....
«N'lne<Wn ill likely to _ inl4!rl'e",,_ LN.o.b and ronnec\.Or$
Ibould be t1ltHrd at the point lllat thfoy enter the~ulpme<lt
clulNia or metal tllbinet.
(Signalle~pI'I'lbICIll5 may oriKinate from _nild;rf~1
IO\IF"I'e&.E~h1eW«e problem mllit be~individually,
'*' mIY I'llIllllllioe IlIlY 0'IWlI!IimI.~mentIlntill1l '"the ""'""""
hal,~bK-n COITft'ted.
I bo~.... hr.-ew~lhe~anI.tnna"1l1from
o.TV_
S 1fT\'dwIM1!iI_"'Il'rely aft«l.ed. inMaI1 an1I'Jl~_PMll
1Uter. If one tw ab"Nd)' boom~lr)'.~lhrM or ra..r
I ...... Ii the I.ISnIIlIiW!r~~alnl __ the~t.IIrouglI •
~lOI<lidIJ~'J'hr,~f'rom • diIearded TV cWIfttion)'Olot' or
Ib't-k .......uo...... be ........c.:.r...,..,...,2 He_.dciol,r..
SECTION T.....O
RESOLVlSG1~7ERFERENCEATTUE TELEVISION RECEI\'ER
Rt.o Oew 1M MlnIonnation to TV Owner"' MC:tioa ... ,..e 6~thM twx! 
book. DKt'rmIDe..tw.~)"lUI'"~!1M~to MIp I"I"tOln! 1M
intM_plobieilL IftMy '-'" not tried Ul)'~the_odedlION 
lion&, I'IMew the IeCtioft menlillMd Ilboo'e and try the~
l!OIution& Theft:
I Prior to 'M.lflring on W TV I'K'eiwr, tI)' to deuonnine W~~the
Itll.erfeftllee and its frequent)'. Ifthe1tl~rl"e"';llgfl"f!(jllMC)' ill on 01'
lIN/' the TVItl~nne<liaufl"f!(jl'entY (I Fl fl"f!(juency (bel..ftn 1lppI'llll'
~ly.f,1and 47 MHz,),p~dirertJyto SI.ep 7.~'orFill bn.-.d<a8t
interference. proeeed to S,,*,\. 10, For 50 to 54 Mfb~ll\.IleUr
jn~rferelll'<!,pl'llCEed to Swp 8. Ir lhe intfffereTlCt! i. not on .ny of
thep~ingfmquende., try theM MIlt t.hree~
• Dillconned. the-n~fIJUllelld from the TV """,iver. If lhe """,j\'er
~tot.heinterferi,..~_hilet.he~.~
inull-n AI;; Il"""r line RF' l\lter.~.."ill help~ilt.he RF'
fl\lm the tranunitl.er ill el1lerine" 1M~rilo the JlO""er rord
b llIIUll.line filter "'hidl)'Oll~either purdlueOl'COIlItn>(l by
roooo.irw; the delnatit Itl~I.
r-II::::;~.."'~...'....
- 0:... "'."'''<0''__
..._.
Fig, 1
43
44
~Try ..-npping lhree 00" four tllmllllthe TV eel"~Nrd-. 
the m-iII ltIroufIh • rerrite torodial a:lre.~I!lft from I dia 
eaI"ded TV~)'ObI or n)'badc ll'alIlIfcnneor can bf, '--' 
CofttI~aJ.o ..'ailable eonunertialIy.
2 n.e~may Itm tonlillue to It...... 10 the iJurffring sipaI.
fNell .rilll tMJlO"ft' tine ftlWr instaDod and the reft'ivinc _ di& 
~Wben IAilI h.pptne. the Il't itMII'i&'«l!i.iJrc theirurlerirw
airnaI dirftlly IMlugIl ita intemIII""ipOOlelU. t.ol* InRde the Il't fo:r.
• E......_alrep;tU work that .....~...-\thoII~replocinglhe
let'. meul 4hieldll or~ReiNtall t.hem .. nee ""Y.
b Thner defeo:u. A_l1.aln tt..t tM tuner.
-;1 properl)' il1l5l.1.l1ed
_haa ill llhielding int.llct
-lias couial CIIhl.,. ;n\.aCt...
If ne<!uary. rvpalr or repl8ce the tuner.
3 If)'OIl do no!: nnd any de(ert.I but the problem penUu. lly inIulling
• lIicll-paM filler (or • tnop luned to theif!u,rft'rir\r~)diro!c:lly aI
the tuner input terminal-.
• See P-C";fI) III tlIiI hallCllook for Illtft W.. "ion about 1IIun.
u. hich ..... lUte'I'lI "iOI Llle pl"OpeI' nltdl'(~.If. proper
hich~~do;,.. noI:~..,n-.o-. ...~theft insUJl
I1ro filte'1'l1 in IeriK.
5 R«onned. the antMnL It'lllKh-~fiItft" hu1l1rMd)' t-ninIuDed.
and the interference contlnUlN, replace the 300 ohm lwin-Ind wire
"';tll~cable. Be~to iMtal1 balun b'wlet_raw~...r
_.
, lrthe InW'fere.-oorrtinuet., loop about 3 or 4 tlllTlllllthe toUiaI cable
near the chaa.sill throllJS'l\ • fenite toroidal oore. The oore from •
dioor.rdell TV o:k.fle<.'l.ion yuke or nybal'k t....wol'll>er CllI'I 00u~.
Co",. an! also available oommerdall)". An Ioddltional fenile l'OI'I',
around ....1I;.,h tile po....er 00"1 illooped,~a1!1O be 1le11lful.
7~rmlne,,·!lether thein~rfe""""",,ill afl'ediJl« all TV mannell. If lKI,
it~be callWd by the interfering lima! bei,.. on tM IWIle
fnoql>tncy llIl tM ...-i'-':'-·I inlerrnediate I'reqIlelXY (lf). Rftelwr- IF
interltftnl'f! only omlrIwhen the interf...n,..1ilpIaI1leI between -11-.17
MHI. lbe molteIf~....,. to <I'd_'.e tM II" interference
prolMan iI ..... iliat_ the TV 1icnal1e\'l!:I rNll.-. ..... the interim.
IIiplJ.. Thill iI a«omplished by:
• h...I1..;"" of t..-pI and i'iIten ..... eliminlte~and
...-Mr 0\'l!:rbdiJl« by the~sIpaII. and
• U....hiP pirlarutlmland.....~the IeYeI
ofTV "'-.!he..-i,WIantennatemlinIlII-'" ......
out the interfenncllo ThiI tedlniqloe doeiI no( eIiminMe the
inurferenee but ....y reduce it ..... I Irvel w/Uch iI IIOl
~ornotllOljceehle.
8 Another t)ope.ol itIterfeftnce from I nearby rlldio uw.mR\eI' illIIIiqlll!
..... IN! InW.€ilr 6 inetl!r band, 5O-li4 MHz. ThiI band illmll'lll!dial.ely
I(lj-eenl ..... TV Ckannell!. 1b .....-01"". inIlaIll high.paII filter "ilJI •
""t<Jtf frequency It 54 MHz. Two nItel'll 1lIIY be 1leC'''''1. 'try
connecting lhem richl. tM W1let'iIlput tennlnal& I(you iMullthem
el8e\o'here I,lIle lhielded,lbort lead&. You might IiIo tl')" repoIitioning
the TV~teru.-farther .....'J,)' from the lr'anImil1.er- antenna.
9 If theinteri~..,nceron~inlJ8after t.hetie meMUn!1I., you must refer lJ)
the 1\lCt!1vcr lel'\'ioo~Checl< each 8UIg1: fCll' the\1III~1rfllIJOOIll.
[..o'1g 1(,ads to~"'-.>d ludio ",,11,1100 or Olher roI1tro1. IU"t! likely to
pkk I,Ip I,In"..nted lllgnaI& Bypassing with c:alJllcitOri lJ) lhe chaililil
-.>d the ahieldine «long leads oI'lcn elintiNOtft fil<'h ligna!..
10 lbereare _ro.l dill'e...",t ...~~FM BI'lJOldellll~1lIIY interim.
with televilion I"\!<"tpt;"":
• An~I"M sution operating below 90 MH& 1lIIY int.erfere
onI)' wilh TV Channel 6. (R..r.... to~1S .)
b An FM~lter'in W irnmtdiM.e vicinity 1lIIY _
blanWtinr ol !he TV l'l!ari>-.:r. The TV rKeplion 1lIIY appear 
-.II. wilJI or...nhoul~iIurleftftClt J*u....
C w.... TV~ito ltx2ted nNl' an I"M tnlIlIIIIIiuer-. !he
~TV ..tiD freqJl1k) (RFl and milI<itr ItIflft-. l\DKtinn
in...tNt produce-.edintert* SpUl 'nUl ilGftftI mft' 
red \0 .. I'ftei__~hIu _Iir:&
45
46
11ThellOllltionAtolhe"'~1INlt'M~~~arr.
• nl inl.erfe.~o>ceto TV Chanrw:l6 can tJt, eIimiMt.ed by Nl.aIlin«
•t~I"M~ttap. l'wIiJw~the U'ap is critieal.
~.tune it to u.e irurlmng r» __',t~.
"~inl.em. uncan III!~by inItaIlinc: ..1"" band
...jM.ion filter in the Ult.eMll1iJle or~• lllllllbll! FM tnp.
~~iver~edIIarmoni<'s irI the RF input or mi:l:B lugescan
III! io:Ienti1"l£'d by the following \"'0 methoo:lf;
lm"""- • """"... attf:flluation in the .men... ref:dline.
M.......... whether the hanDonir lm-elln then!<'l!:i\'~riA .....unod
by more thin the amount fI attentllllUon ilW!rted. It 10, \.he
harmoniCll ..... being~nel'lOteClby the~h·er.
;1 U... t>IU TV re<!ei\'l!rlI that aN! ditl'erent m.kef. 'J'I'M'y ahGuld
both he the _ IYJIO! - /:ill..... ""lor OJ' b1lock and while A
.'O!<:eh.....~edhal'TJl(Nlk ill unIiRly to appear at the wne
inleMil)' in \"'0 di"erent rec:ei_
Thc:on'ed.reeeiYel'~I~harmonics, ilwaIllUI I'M t.nd
~fiIW" or. lllllaUe trap (umed 10 the interfering
--'I~
SECTION THREE
ELECTRICAL. I'M AND AUDIO IN'rER}'ERt:NCE
RESOLVING ELECTRICAL INTEKFERENCE
Beforeptoc~I'ftd the~tiocoon .-ce II. It )QII '-...
~lboee ...... ,.,.. Mauld a1.--ly~the~fII the
--.
WARNL"\G: Chedr; IoeaI eIftt.ricaI c:odes to determine irthe~.....,.
be IIlOdified, and wbeU>er it I'IUItbe moditied br • kuad
~Mndjfjc:wrion& that.........~wit.hc.pa.
dun should be eompleted with ettftme cart! to p....-t
the~unfrom Ibortinc out the /1£ line. AYOID
WIRlNG THAT COlJLJJ CONDUcr THE FULL AC
UNE YOu:tGE ro THE CASE OF THE DEVICE.
UN£ YOu:tGE ON THE EXTERIOR OF DEVICES
CAN BE LETHAL.
ELECTJUC DRILLS, SAWS, MIXERS OR HAIR DRYERS
lnt.erferenee from electric drills and saws Is usually brie{, You probably
ahould not modil'y them. MOOilIcati0n8~.be dimcult ami tirne-«llllluming,
It JMdiI"ICa!.lo<wJ~required, the following infurmal.lon~beIIMSistanoe
1 Drills, sa....s, rJI!Mo,F1l, hair df}'O!l'S and other o:\evleftl that use • limple
ACIDC motor UlIually c:lluse inte"ferenre.~Int.erl~lQuh.ll
from arcinc bel.'Nftn the bruMes and eommutator. The int.erle""ntII'
ia lhen tnrwmltted lhrouch the p""....r rord llI>d I'lIdiated by the cord
and ,,""';ated building ....uing~Moo. moton ..... wWd in
.el'ift, with the Ileld roiIa ClOlIJ'Iet't.f! between -" brush and the
PG""e'T line. Field C'Oib help to i80bu the~bruIhM from the
P""ft' tine. The follow\ng -.TN .....,. be ueed to IIlOlTeCt lhia type
01 irterl'erena.
• So6der. 0.001 mfd dial: «nJ!lic~torbetween NCh bnIsh
hIIldK and the motor I'rwJw, usiIw the IiloneIt po 7--.nectine
lNda.~wah. ntiDg 011,000 ¥OM"", pre(el'llble. Do
not \1M~with leu o.n. lllO .... ...u..
47
48
II If addltk>nal at.!(orlluabon ;.~ulred.ronnert additional 0.001
mfd diM= teramit nopaciton be\..ftll -.iI side~lhe llO"'er liN
and tile mo«>r fl'lllM. PIa<:e thoem u r'-'..polISI'ble to the point
wbel'll tile po..',,,r wi",g enter the motor enclcNlure.
r Very lhon k-alk be\,,_n the rapadlOr Md motor frvne an!
etIllentillLlfthe motor~operMedin agrounded1lIl.'tallic~
thew n!COllImenood cspacilo'" IIJIould redlll:e the lnl"rf"",,,,,,, to
1m Il1mQllt lllliudibl" level.
TlIERMOSTATS
$orTl(,otllTlt'8 Iho:rmoiItatkll.lly rolltn/lleod <Io!vkK _II all e1ed.ric blankeu,
rllllllll1\k helteTl\ and home lMlatina*oollllll unilt COlUIe interference Thill
type~imerfer<>nc:e ill <:&U*!d by amrw at \.he «JflI.Kt poinU. Am,... rwulllI
from "itbel' wom oontaeU or (alillft 01 the IIIap~~w
element to exert eTlOlIllh JlI'"'lU"' OIIlhec:on~to preyent urirlr- Th <or'
rtetthi~lyptl or inter1'ere"",,:
..Sp~~I.actdeanudin!<:tly on the mnl.llotU ifpouibIe. Thill ia •
temporat)' meuure.
bRepl~the thermootatir ..,ntrol unit.
DIMMER OR COMBINATION COllo'TROLS ANU SWITCIIES
Li,rhl dimmer rontnh or «lrlIbinllllon~and IJIO'il.cllM Ilia! utiliw
SCR or triaa can prodllCt!lnterrere~Tbl8 I. dl.llllo the Vl!ryI~PWlI''e
frontp~~.tile Pitching lit the sca or trt.e. Light dirnJ1'ler eon·
trolA do not oIUn .,._ Uo.....·iYon Interfero!flMH",,~,lhPy do ClU_
Itl'Oll(" AM brolOdta3t Int.erf"l'el'lO!! which mq be diI!Icult to fOmple«'ly
"llm;llIu,,-
B)'p&&lling In tile rrIIlIUIer .00...., in .'lru"' 2 rna,)' be helpful.
Fig. 2
ELECTRICAL INTEJU'ERENCE CONDUCTED Dr THIo: POWER
LINE
Th eIiminale~inlerference~by lhe~line. iMtalI a
JlI"ftT'tine ftltft" Itthe inlerfeten«__Ilene,er poWNe~rline
filUon~mI)Il «f«uw "'heft~at the _ allhe~llft
nthertJ.nallhe deriee 1"llClri\'" the ir&erltftAtll. Few beIl-.lU...-..
1m. lihen 8houId be~rigllt It the~IIpfIIlanoe with the
MorteIt P'llrl:1e line cvnl OUs wise, direc:t '*""_ from the line eon!
1IetWftI the _ and the fiIW' wiU he troutl: eIfiC iaIl7 at VHF
'-
SUlOIARY
E~~rfel"l!t'ftillaho~belIl mntrolIed byftI~~and
~~udoR u~1)IetoilfI-.-WhefI~elenrir:III
inI.eriema)OlI1bouId.,Roep in milId thol the JIlMW liIl.ribul.iOfll)'lltftll
CIU'liE,.... f, \1VIImIlanclradiau~ilu,1e,c,_ SudIbUrf_
m.y~.unILvIII thetypl!~bydefediYe~~
J\>oow line ifMrlere-. 18 fnqllefltly ....-d by tnle branc:hN and r<'lib«e
\.hal comet in «ll'ltaCt with higll volt..,go! linell, def«tlve dlItribution
trvIAf'ol"ll1e'l'a, cimlit!In>akI,..,lightni,.~or J)(IWer line illlU\al.on.
Sueh interference o:aru'IOl be l"eIOl\'ed by the 8l"rvke tee:hniclan, Report it
to lhe po....er rompan)'. Sometime. lhe dirterenliation of
appllllntO! If'''Ml1lled and llO"....r line p""ntede~int.erferenoe
IIOI1f'l:etI nuo,y be dimc:ult, Yo)II...-y need \.0 have power company lel'Vioo pel'
IlOn~lllmlllClghborhoo<lrellidenU! oooperare to Identify the llOIll't'e of the
problem.
FM BKOADCAST RECEIVER INTERFERENCE
FM l'ft'II!iver interle_ ill not 18 rommon M TVInl.erf~_The
.......,....-er !.t&lwh.idth cl FM~...... toopled with lJIeir ....perior
nDiBe l"t,jertion~itieJmakH them leN IllllCl!pUbie to~I'ftfft
than TV~V\'...H_....hen flOI''er line or Olher electrical
interft'mlft ill~elnlt'llr. it ma)' interfe... with rM u well .. TV
~'''en.
z Poruble f)f .-i""rI with ..ellcon~antoi'nnu ml\Y ,...ponot to
~~GIl the image I'requenq. -"..l'INrbf airmott 1'hi&
;.~• --......obltlll~IINZ" airp'JI1& When it..an cutaide
..........,. will helpIO~'"the~"LIt IIIl\)' a1Io be.. ...,. to
inIlaII. 'UMble ftM,.(tmoed to t.be inl.etf..,ilc eipaI) In the_
-
49
50
3 CD and amateur hannoniaI may ........wnallyintene~with ceruin
_ionI. HatmOIIiaI eaIl be eIlmina«od only • the olfendirw~
4~in tJw, ririnily~.1Ii«hp(JIO~....~~
~be1.rOu~luoiJleand difl'M:llIt 10 mmpIetely Grr'et'L BIanketins
mq_ ...l'ftIPivl!r aMitivityorlimit 1'eCll!fII.ion 10 \hI!_1lr'Or\g
1oeaI1Ution. aD poinU on the dUllI~~be rM! ry to18Oh~
the poblet" by inBuIling an~_ and. nojection rilt.ft"
tunfd 10 theloc:II-x..',~n.;........ IOOl be ftIlimy atiH.....
lory .;nee the filter ...,. alto block Olher IWiona in the p&l't al the
bl<*kut band _ the~IocaIItation.
AUDIO INTER.'ERENCE
Audio inlerlerelW "' defined u the reception III wtWarlU!d radior~
cy (RF1 aicnab or enero by an llI.'dio ampIiIler or U'anIdl>m'. 1lIis
~bIe~OC'I:llI"ll"Nn !he RF~lit~.edby any U
the ton'IpOflIrnll cw -.ditionl~bIolow:
.........
-tnnIiMonl and .'Wi8ton
-in~cirroita
-electron lubell
-poor IOiller jointa or
_(aulty ground oonnectiolUl
The deteCWd elgna]i~th('n pid",d up by IIw! .udlo o;!evio:f, andp~
alOlljf ...·lth thedt'~ired~ignlll.
The ef'fl.'Ctll of audio interference ,'at')' acronlil1Sl' \.0 lhe type u modulWon
emplo:Yo:d by the interfering tTan!lmitl.el'" ..tol~
AM The \-,};.", Or musk will be heard u atlY nonnaI audio .ignal
applied to the amplifier. Theinterf~IlprJ may be ex·
t.remely loud and alig\U.ly diJtoned.
SSB On ei,.,p. IIideband. the ......... ..ill .....nd prbled and
uninl.t'lligible.
FM UaaalIy no .....md ...iII be bevd but tbe ampIiroen vdume
..ill deer _ ..'hen the i1urlfti!lc I1'alliIll'Iiu. ;. on. CIidt&
may be '-I'd "'hen • I_V U'WlImitler "' Ryoed and
--
T\' The audio f'Klif"ocation III.TV IigrW .;n maR • kIud buzz·
iIlc noiIe. The buzz riI c!laIlce .. the TV pKtlltl!~
I 1b ....aveaudio intm'_you &houId tint .lempl to mte where
the rectit\cal.ion IItakinc place in the alK!io fhain.~'irst,determine if
adjUltilllf the volwne c:onr.rol etren. the~~~n!_
• Ir the~_(f/ the irurlBing IIignaI~..lIM the volume
<.'OIltnlI ia.-eel.. wn the rec:titlcation II t&kin« pIKe BEf'ORE
"""""""-
b If InO'I'iIw the votume ICOl'1l.Nl hal minimal or no etrect. the
~II~AfTER W ¥Olwne coriU'Ol
! P"..ad Lo the .oppmpriale -. u .......... CIUtliJwd ...lr tJoeooe
dutionlI del not rnoh'l! lhe audio irurlE.tidpr~m.contac\ lbe
manufldllt'er I'oir runher ·ssjoll_
• R«ti,fiallw. BEFORE IAe ""'__~rol.The~to ..-.I..u.:
audio r«ti1\ca1ion ....~~fIOIU>«tionI.~
and RF~~A"Pi~01 ..1irniMUon~~hm\lSt
often be 1IWd. A~input audio amplifier Inr.Y be~
to .1Ktio Inlerfeftfll.'e 01'1 one or ...."ft"lOI 01 the .vallable inpuu.
Low Je\·el. high impe<\allce input.I. well .. I.hoee for wmuble
c::artridget., !.ape beada and rnierop/lOnelI are moM~'ble.f'or
~the only inputatr~may be from • t\lmlable. 'Nhetllhil
0l'ftIn, diIlronne<t theI~~from theampl~'1input
terminal. If the interferenoe ltopll. the R.' illellled by either tile
cartridge or the wi,." between the~ll/ld~heamplifier.
If It u. due to broken or detective~hie1dj"3'on the wiP'e,n!P~or
repair the wit"l', If the RF is picked up din.ctly It the eartridgo>.
il\llt.all • IlTIlIll HI" dlake and bypaIIlI eapacltor. Be 5n!i'u1 \.0 not
\lnbalance the plck·up annor not UlIe componentl that. will thange
!.he fftqueM)' ""JlOnae u the l)'Stem.
bR«j\fiaat~ItJiTER I4e ""',,_ l.'llIUroL Iw:ljultina lhe volume
<.'OIltnlI -wIy will not a1f1'd. the int.erfemlCe '-I. When t.his
happtr-. the RF'"cnaI is~wingthe dmQl bel....~nthe mIume
IlOntIQ/ and the amplhr autput u.nninah. 8e(in to ton'ed. thM
ploblem by dlecltiIlc for IInIbieIded Iolw IMdt to • YOhime ClOl'IltOl.
The HI" Blgr.I ........ be bbiotd by~or~.thepoinL
01 entry. II iI importanl thM. the COIIIpOIM'IlU wIec.ud torlIJ~ring
do not alterthe~.audio~
51
52
~Grvoaodu.,.WhelJler~~grounding.~
~,odIu~W IYJle III eqwpllom. irMllwd. )l0It~
.'hid! is IIIJl~"il1I. t!lrM wire .-oer cord Ib:IuId'-~iu
d-..io and eabinet grounded wtth ..~I""JUnd~
It is generally laislO__.nI"".10 .. cood.nllf"lU"d,
Iud! &II .. rnftaIliot waUT pipe .... dri¥ell 8 r- JI'IUDCI rvd.
d A gJ'OUIXI ..·hidI ill~(or AC IJlI"'W IIIIl1 not be .. rood
lJI'O'.Ind tor hi«!- ndio~A ITO""d wire~dbe q
-.ugh to ll<'l &II ..~_ Good RF~can
~nmaIlybe ..:me-I by UBI! of low induo:tanofe~(~
1Itnlp), bondinc ¥ariouI equipmenu to Neh other -'lor .. good
earth ground.
CAUTION: BEFORE GRQUNl)JA'G. MIlKE CEHTtHN THAT THE
EQUIPMENT lJQES NUl' HAVE ONI.: SlOE: OF ITS
POWER LINE CONNECTED TO ITS CHASSIS. IF IT
DOES. GROUNDING THE CHA.$SIS~l)UWBE
HAZARDOUS AND COULD RESVLT IN OYER 
UMDEO ELECTRICAL CIRCUITS.
" Some~-.r be ntud with .. thft,e Illll'Idurtor powl'l' cord
This typeot equipment~ha\~the~mnchx!or ofiu
I'O"'~cord~yftIorInl!ded to ita chaIeiI Mel eabiIlet rd the
Nbinet ill metal). ThiIt~01 equipmtnt~not need to be
I"CJUIIded~.Al~..~If'OIlIld to IlIdl equip 
menl mirI:t n!IUIllD the IOrmation ct .. uound loop. AI"JUDlI bJp
mq~'al.eany iru.",tI_Ground loop; _ eb Cd' tMt"-"
zero IX: pot.ential bK.'ft!l poinuI but IIIIl1 havt!~AC or RP
pcuntial bet_poir\l.IIlO alIoor ACor RP NJTeltIi 10 lIow. When
....iMrw"grou~and bmldinIcml'l!'Ction~taR~
to lIVOid creatire' f"l'WId IoopI.
I'1guI"e 3 aho\oll the P""Ptr and impropl'f method. olgTOUndinc
romponellt.&
G....I... Cintiu
ltll, "Ioo!l" m.,-el
11II., .......1...11•
.. -...fr.-q_,
53
'ia"
.-
Fig. 3
54
r 1:lef0l"ll a<:t.uaUy~i'lf.gn.>UJld 1./1 any fqU!llnleIll. rnNlI1ln! the
,'Olt.ap bet,,-.. lhe dIaMisand iPOOnd. 1llkIe~1"l!!lle1lUwith
the equipment on .nd otr. lr llIl)'.~WIlltar if (IIUnd
bet"'Hn the ehallllit to be If"lUnded and 11M! .......nd wire.
dt"-"nnine 1M'~\.alI1'IOUroe bl1fore making the rotlneaion.
CAUTION: SO.tll.: EqUJPM£.VTCHASSIS ARE ATUfW-: IULDIoG£
Pm'ENTIAL AND CANfl,'qr 8F. CO,v.vECTI:O DJRJ.'Cf'.
LY 1'0 GROUND. IN THESE CIRCUMSTANCES, A
CEIUM/C CAPAC/roR OF 0.001 MFO AT I NV
SIiOULO HE PLACED IN 1'111; GROUND L&Hl TillS
CAPACITOR ACTSAS A SIIQRT TO NF SlITANOPEN
CIRCUIT TO TilE 60 HZ POWER LINE.
&' SHI£LDlNG. All~r'-"~1./1 aud1IIequ~nt
IIhouId c:<lMist or two eonduetor wiJ'8 with • l!l!pan.le Bhield. The
ohleld .houJd be grourlded ONI.Y III tho! amplitler end, and
-"'>old not be~U &11audio~.The \..."~~
ahould be connect.ed to the ......
h POWER LINE: FILTER. RF rn8,Yenl.eT the ludiGdtMoe l!u'uoJih
lIM: AC p<'1\'o'er line. There llI"e llfl\'t'I"ll1l.'01lU1'>e1'Ciy ....ailable bnndll
01 pOI.,..,r line lIlte.... A power line tllter located III • WlI1l ou!.let will
not preo"1!f\l. RF pickup by the line oord between t.he fllter and t.he
amplirler. A JlCM'tr line filter audl u the one shown in I"ipre 1on
pItte U tNJ' be mnatnlCUd when.lee ,eoy. J"Iac,e t.he 1\Il.l'r U
doee all poIl5ible 1./1 the point whtre t.he AC t(lro enter'll the
amplifier.
I POOR ELECTRICA.L CONNECTIONS.RIorllCllder~
or old eIectrolytie~""'1' _ an aOOIo RlrtitIatIon
problml. If allp~t~""\'e falled, t.ry l"HOldering.u-..
nIldioruI In the ampliller. Al80 I'fJlllKe e1ectrolytk caplciton. Belonl
lK'UIally repladng llIl elect.rolytk~r,tJ'J' para1Ieling !.he
0f'ieirW \':lIpI'ritor wIth.. properly funrtioniJc capaCtor 0I1ikie vallie.
ThiA~dI"l<'"ftI llIl)' bad c:apadt.or.
TRANSiSTOR EQUIPMENT
Rt' detection U8U&lly 0ClC\lI'& in the inpu.t dmtlts 01 amplil'ier& It can UIU&Ily
be eliminated by lhe II.... 01 • Mllni rapldlor, all~'1lIn PigIIre 4.
A resi:ator eapIIdt.or rombinalion may al80 be lIIled .. ahown in F"ig\ln! 6 
Make &\1.1'0I tllat the IDter nel"'lll'lt you IIlIe does flOC. effe<:l the ll'aJI8iator
bwlng Ort~amplifier" (1'I!q""nc:y~
55
CItpciWr..u.-'"not cftUr;alH"'h~.~CIf*iton In bnt.
~or pIutX capIlCit.orI '" not ..~ertift... bn' ',. RF due to
intenIllI and Ielld indI .... _
5....t Cap.dlor
8"....i1lC
 
•
".
 •
FIQ.4
:
-r b'
: 00'.' T
L ±-.•
1..-lI-'-Idbe Rpt..1Ihort u ," 1Ae MJW'i'lly with bypaaI~
The Ielld \erwth~lhe reIOlWll !l"eql.lelll:}'. and~(ln',the
~<!CtiwnHll~b)'J)Iainc.B~diT«tly t.o lhe ftIIitter IIdI.erI~
f'fl'«tlve.
Connections to thec~or other grounda IIUl,Y !lave more induced R.'
than tbe algnaI koad. Ifthe lnterferenee incI eaaee. • ground \oop Iw been
eftlted. WIlen thiB l\appelll, ll'y the inductor method. Seoe F'igure 6.
T
Fig. 6
I.Smt+~·up10 20 MH'
SOIl~Hr' 20 10 50 MH,
HID~M~·5010 500 MM,
56
ELECTRONIC ORGANS
Ol'llan circuits tan be ilolated by ulinc th .well ptdol. bandbo~vol.
\11M, or u.b- (drew bBnJ. By adju1linc each oflhue COIllrOl. individ 
uaUy, you tan obH.....e their Tftpecl.ive elTen on interfere".,., If !.he
volume of tho interference chanr•• when II conlrol ;1 OdjUlted, t.h,
RY i. bein,r del.el;ted by the ampliner somewhere before thn oontrol.
'fthe volume of the interference don not chlU1&e, tha int.=rl'erenu i.
heinl:d~fICtedafter thal conlrol.
U.e this method to determine where the RF i.~urin(the IIrpn.
Then inlflrt the proper liIler in the appropriate drtUll.
TELEPHONES
See the fCC bunatin entitled, "Telephona Interference" for furthu
;nr....matlon.
ADDITIONAL fNFORMATION for "",...loe technldansobout~Iolv­
in, interference II available from lor.l librariea and t.edlnical book •
•tores. Handbookt are aiiO available from:
ElectTonic lnd....tria AQOciat;on tElA)
2001 Pnln.,lvanil AVetlUll, N.W.
WlIlIhinllOn, D.C. 20006
American RadiI> RetlY~ecARRLI
2U Main Streel
Newintton. C<>nnectlcllt 0611 J